A fast-acting cycling instructor, a team of doctors and a new heart pump saved Curtis Broome's life.
I. Skull Cap
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There was a chill in the air the morning Curtis Broome, his wife Heather and several friends met to bike the hills above San Francisco Bay. Chilly enough for Curtis to put on a skull cap.
The skull cap made his bike helmet sit high on his head. Heather thought he looked silly, so she took a photo of him.
“It was just Curt being Curt,” Heather said.
Later that day, Heather would gaze at that photo then hold it close to her chest, all the while pleading with her husband to fight – fight for his life.
Curtis and Heather shared a passion for biking. It was through biking that they found their passion for each other. When they weren’t biking, they would walk four to five miles through the Bay Area hills every other day. They were in great shape.
They found exercising together was good for their health and their relationship, and it helped relieve the stress of their demanding careers. Curtis, 47, was a hard-driving Silicon Valley entrepreneur who founded and ran an e-commerce network that worked with most of the major wireless providers in the U.S. Heather, 38, ran a successful executive search practice that specialized in finding talent for high-growth software and internet companies and venture capitalists. Together they also had founded a technology networking organization for the alumni of University of California, Berkeley.
|The day that changed their lives started out “as normal as normal could be.” Heather took this photo the morning that Curtis suffered his heart event. She found herself clinging to this photo later, as Curtis and his team of doctors and nurses fought to save his life.
They had put off starting a family due to their demanding careers.
The cyclists set off down the Moraga Road toward the San Pablo Dam Road that Saturday morning, May 26. They had set off to ride a loop called the Three Bears – named for the three hills along the way, each a bear to climb.
Curtis was lagging a bit behind the pace that day. His wearable heart monitor had warned him to slow down as his heart was beginning to beat too fast, even though he felt fine. Nine months earlier, Curtis had had a sudden spike in his cholesterol – enough to make Heather a bit more watchful, especially when he was engaged in strenuous exercise. He had started wearing a heart monitor when he exercised, and sometimes his blood pressure spiked high.
“He often pushes himself pretty hard and I didn’t want him to overdo it,” she said.
So Heather pulled over to wait for him to catch up.
They met, and she rode with him through the descent of Moraga Road, where they reached speeds of over 30 miles per hour.
They stopped at a stop light in downtown Orinda. They had ridden for about five miles. Heather was on Curtis’s right and the traffic was on his left. Looking over his shoulder at the oncoming traffic, Curtis started to sprint into traffic.
“We were starting to roll again and we had to veer left, but he was veering very sharply,” Heather said. “Then I looked over at him.”
She saw her husband’s head drop down. His bike crashed in the middle of the road. Curtis wasn’t moving.
Darlene Vendegna-Guare, an indoor cycling instructor at the downtown Berkeley YMCA and a part-time coach for road cyclists, was out riding with her group. They were going up a bike path that paralleled another path at the bottom of the hill. Darlene had stayed behind to help one of her cyclists with mechanical problems when, from the bike path down the hill, she heard a bike crash. Probably someone clipped into their bike pedals who couldn’t maintain their balance, she thought.
“I figured that someone had just bruised their butt – or their ego.” Darlene said.
Then she heard a scream: “No! No! Noooo!”
Darlene ran down the hill. She saw a man lying in the middle of the road, a woman shaking him and shrieking:
“You fight, Curtis! You fight!”
Traffic had stopped. Cyclists had stopped. Someone called 911.
“Do you need help?” Darlene asked the woman.
“Yes, my husband is having a heart attack!”
Darlene disconnected Curtis’s toes from the clips on his bike. He was having trouble breathing so she started pumping his chest and breathing for him. She had learned cardiopulmonary resuscitation (CPR) as part of her job at the Y, getting retrained every two years.
“I had never had to do CPR in a situation like that before,” Darlene said.
|Heather kept a diary throughout her husband’s recovery. She documented his day-to-day progress and the many people who helped along the way.
From an overpass, the rest of Darlene’s biking crew – about 30 people – watched the scene. So did those who were waiting at a nearby Bay Area Rapid Transit (BART) station. They watched Darlene work on Curtis – it seemed he was able to get a few breaths in – and they waited for the ambulance to arrive.
As it turned out, a fire station was just a few blocks away, so help arrived in about five minutes. Two emergency medical technicians (EMTs) got out to assess the situation. They checked Curtis’s vital signs and gave him CPR. Heather continued to shout, “Fight, Baby, fight!”
“Ma’am, you need to step away,” one of the EMTs said to Heather.
They shocked Curtis with an automated external defibrillator (AED). His heart did not respond. They did it three more times, same result. They gave him three shots of epinephrine (adrenaline) to open his airways and constrict his blood vessels. That didn’t work either.
They would not allow Heather to accompany him to the hospital – there wasn’t enough room, they told her. As they put Curtis on a stretcher and rolled him to the ambulance, Heather saw his arm roll off and his head roll back. I thought I would collapse and die myself, Heather wrote in her diary.
As they took him away, she thought over and over again: He can’t die now!
Not now that he was going to be a father.
|Darlene, Curtis’s CPR Angel, celebrated his amazing recovery with him
Curtis was in cardiogenic shock, which meant that his heart suddenly could not pump enough blood to meet his body's needs. A rare condition, cardiogenic shock affects about 40,000 to 50,000 people a year.1
Curtis had gone into shock due to ventricular fibrillation, when an electrical event caused his heartbeat to become rapid, irregular and unsynchronized. The wild heartbeat led to a sudden cardiac arrest, making the lower chambers of his heart quiver and become ineffective at pumping blood to his body’s vital organs.2 The major cause of death in cardiogenic shock results not only from poor blood flow but also from multi-organ failure.3 For most patients, cardiogenic shock is the result of a heart attack.4
Risk factors for cardiogenic shock include older age, a history of heart attacks or heart failure, coronary artery disease that affects the heart’s major blood vessels, high blood pressure or diabetes.5 Except for occasional high blood pressure, Curtis had none of these risk factors.
In the past, patients in cardiogenic shock were generally considered “lost causes.” Now, if treated immediately, about half survive.6
Curtis had a chance to survive if they could get him to the hospital quickly – very quickly.
III. 50 Minutes of Death
|Next to this photo in Heather’s diary, she wrote “These amazing nurses did CPR on Curt for 50 minutes.” They also assisted as Dr. Chang implanted the Impella 2.5 device that helped stabilize Curtis’s heart.
As a policeman drove her to the hospital, all Heather could think of was her husband, the father of the child inside her, lying on the ground.
It had been just three days since Heather and Curtis got the official verification – she was pregnant.
“We had put it off and put it off,” Heather said. “When we found out, we were ecstatic and thrilled and scared at the same time.”
Heather had seen Curtis crash in the road. His face was so bruised and beaten up that Darlene had to convince the police that they were at the scene of a heart attack, not a hit-and-run.
By the time Heather got to John Muir Medical Center in Walnut Creek, the EMTs had been able to revive Curtis’s pulse, but he remained in very unstable condition.
To help him breathe, they inserted down his throat a breathing tube attached to a respirator. They also started intravenous drips of levophed7 and epinephrine to improve his blood pressure.
Upon arrival in the emergency room (ER), an electrocardiogram (EKG), a test that checks for problems with the heart’s electrical activity, discovered a left bundle branch block, meaning that electrical impulses that control the heartbeat were delayed and made it difficult for his heart to pump blood efficiently. A preliminary echocardiogram (echo) found his heart’s ejection fraction was less than 20 percent. That meant Curtis’s left ventricle was pumping out only one-third of the blood that a normal heart pumps with each beat.8
Heather saw Curtis briefly before they took him to have a computed tomography (CT) scan on his head to see what kind of damage had been done due to the fall before being rushed to the cardiac catheterization laboratory. He was unconscious – but alive.
|Interventional cardiologist Richard Chang, MD, FSCAI, was at a barbecue party when he got the call about Curtis. Dr. Chang wasn’t on call that day, but he knew how to implant the new heart pump that had arrived at the hospital a couple of weeks earlier. He left the barbecue and rushed to the hospital to try to help. Curtis would be the first patient at the hospital to get the new device.
An hour passed during which time Curtis underwent an emergent coronary angiogram, which revealed no acute coronary artery blockages. Given his overall poor heart pumping function, he was transferred out of the lab on full oxygen and multiple medications by continuous IV drip that were barely adequate to sustain his blood pressure. To Heather and her family, that hour was “forever” five times over.
As she sat there with wondering why it was taking so long, one of the ER nurses came running down the hallway. She grabbed Heather’s arm and asked her and another family member to go with her to the ER.
Curtis had broken his left eye socket in four places and damaged the side of his forehead, despite wearing a helmet. He had a blood spot on his brain, and if it got any bigger – since he was on blood thinners, there was a good chance of that – a whole new set of medical procedures would be needed. But those were the least of his problems.
On his way to have a head scan Curtis had a cardiac arrest – his heart had stopped. After 50 minutes of CPR, they had gotten his heart beating again, but it was beating rapidly and the prognosis was bleak.
“He had coded and the nurse wanted us to be there when he died,” Heather said.
The cardiologist told Heather that, in his present state, Curtis had less than an hour to live.
Unless they could help his heart to start pumping again.
The hospital had a new device that could temporarily take over his heart function, but no one working that Saturday knew how to implant it. They would have to call someone in.
It was his only chance.
IV. Pump of Life
Interventional cardiologist Richard Chang, MD, FSCAI, was poolside at a barbecue party that Saturday when he got the call about Curtis. An interventional cardiologist at John Muir Medical Center in Walnut Creek, Dr. Chang wasn’t on call that day, but he knew how to implant a new type of temporary heart pump that had arrived at the hospital a couple of weeks earlier. Curtis would be the first patient at the hospital to get the new device.
The odds were not good. Despite the oxygen Curtis got from a breathing machine, he was not doing well. Despite the multiple intravenous medications, he was not able to maintain an adequate blood pressure. His heart was not pumping. His lungs were filling up with fluid, and his oxygenation was deteriorating despite being on the mechanical ventilator.
“He was actively dying,” Dr. Chang said.
Curtis was wheeled from the intensive care unit back to the cardiac cath lab for the procedure to stabilize his heart.
Dr. Chang implanted the Impella 2.5 to support Curtis’s heart and give it a chance to recover. “If you can maintain the patient’s own heart with advanced technology, that’s always preferable to a heart transplant,” says Dr. Chang. Curtis benefited from the support of first the Impella 2.5 and, later, from the slightly larger pump, the Impella 5.0. You can learn more about implantable heart pumps here.
The new pump was an Impella 2.5, the world’s smallest mechanical cardiovascular support system. Consisting of a tiny pump inside a catheter, the Impella 2.5 was only 5 millimeters in diameter, with an electric motor that could pump about 2.5 liters of blood per minute.9 The new device was small enough to be threaded from his groin artery to his heart’s main pumping chamber. There it would suck blood out of his heart cavity (left ventricle) and pump it through his body. The little pump could support his heart while allowing it to rest and, hopefully, heal.10 If his heart pump function did not adequately recover, Curtis would likely need a heart transplant or surgically implanted left ventricular assist device (LVAD).
“If you can maintain the patient’s own heart with advanced technology, that’s always preferable to a heart transplant,” Dr. Chang said.
As soon as the Impella 2.5 was inserted, there was improvement in Curtis's oxygenation. Less fluid was backing up into Curtis’s lungs, but he still needed full medical and mechanical support. He was immediately transferred to a sister hospital, John Muir Medical Center in Concord, to place a larger version of the Impella that could pump more blood to Curtis’s body – the Impella 5.0.
As the medical staff worked to save her husband, Heather focused on the photo of Curtis in the silly skull cap she had taken that morning. She looked at him, held him close to her chest, pleading with him to keep fighting.
That night, Curtis was placed on a cooling protocol to bring down his core body temperature to minimize the potential brain damage from the cardiac arrest and prolonged resuscitation with CPR. His heart rate and blood pressure were in flux. The Impella 5.0 was sustaining his blood pressure with fewer and fewer requirements from intravenous medications; however, some of his red blood cells were being damaged by the pump. Although lightly sedated, Curtis became agitated by the tube in his throat and started fighting to remove it. Veronica, his nurse, decided to increase the sedative so that he would stop trying to remove it. Curtis continued to be unstable and his blood pressure tanked.
At 2 a.m., Veronica called Dr. Chang back. As they waited for Dr. Chang, Veronica “just held me and cried with me,” Heather said. It wasn’t looking good for Curtis.
Curtis was given more fluids, which helped to repair his red blood cells and improve his blood pressure. He began to stabilize again. An echocardiogram (ultrasound of the heart) showed that the catheter-based Impella 5.0 ventricular assist pump was in the proper position and working fine, but Curtis’s own heart was barely functioning at 10%. Dr. Chang told Heather that the first 72 hours would be the most critical for Curtis. There would likely be a lot of ups and downs.
“He’s very sick and a lot has happened to his body,” Dr. Chang told Heather. “We just need time to assess if his heart will recover and if his neurological function will be intact.”
Would there be enough time?
V. Golden Gate
Curtis credits his survival, and the fact that he didn’t need a heart transplant, to the many “wonderful people” who helped keep him alive and to advances in medical technology. Here he is with Dr. Richard Chang (left) and Dr. Andreas Kamlot (right), who implanted the Impella pumps that supported Curtis's heart and gave it time to heal.
Curtis woke up to see the Golden Gate Bridge through his window.
It was a familiar sight to him – about the only one. He found himself in a strange bed in a strange room surrounded by strange sounds. He had no idea where he was or why he was there. He did know one thing: he really had to go to the bathroom.
He got out of bed and immediately crashed to the hard hospital floor, splitting his ring finger on a nearby lamp. After more than a week in and out of a coma, his muscles had atrophied.
As he lay on the floor, the machines around him beeped and buzzed in panic. A doctor and nurse came running into the room.
“You can’t get up!” they said.
“Who are you?” Curtis replied.
Curtis told them he needed to use the bathroom. They pointed out that the catheter attached to him made that unnecessary. He looked at himself, and saw he was hooked up to numerous machines, including a heart monitoring system.
Heather, who had stepped away, hurried back to his room. She told Curtis that he had fallen off his bike and was in the cardiac intensive care unit (ICU) at the University of California San Francisco (UCSF) Medical Center. That calmed him down.
She didn’t tell him the full story. She didn’t think he was ready for it. He would find out soon enough.
In addition to his broken eye socket and dysfunctional heart, Curtis would soon learn that he had compromised kidney and lung function. He had been transferred to UCSF Medical Center because his heart wasn’t improving enough on its own, and they might have to implant a LVAD – a permanent and different artificial heart than the Impella that would have to be implanted surgically until a matching donor heart could be found.
Curtis was still in rough shape. His heart needed assistance to keep pumping. He needed a respirator to help him breathe and dialysis to help his kidneys function, which had shut down when his heart stopped. The doctors were worried he might need dialysis for the rest of his life.
His heart had remained the biggest question-mark. Could it recover on its own or should Curtis be put on the heart transplant list?
A key milestone would be if his heart could reach or exceed an ejection fraction of 25 percent. It was only up to 13 percent, according to the latest echocardiogram. They would do one last test. If there was no improvement, Curtis would need an LVAD to support his heart while he waited for a transplant.
A transplant would pose a number of drawbacks. Finding a donor heart is difficult – the donor would have to be a brain-dead person on life support who was a close match to the Curtis’s tissue type to minimize rejection.11 In addition to the usual risks of surgery and anesthesia, a heart transplant would put Curtis at risk for blood clots, heart attack, stroke, heart rhythm problems, severe coronary artery disease and wound infections. He would face a lifetime of taking anti-rejection drugs that can cause damage to the kidneys, liver, or other organs; cancer; high cholesterol, diabetes, and bone thinning; and increased risk for infections. Even with anti-rejection drugs, his body could still reject the new heart. Finally, Curtis would inevitably need a new heart in 10 years or so.
A lot was riding on one echo. On June 1, his ejection fraction came back at nearly 30 percent. The Impella heart pump was doing its job, enabling his heart to heal. Curtis would likely not need a transplant after all.
Curtis made progress on other fronts as well: His lungs were getting better so the breathing tube was removed.
Curtis had been through much by the time he woke up to see the Golden Gate Bridge, his first post-crash memory. But there was more to be done before he could go home.
Although they suspected that stress had triggered his heart to go into arrhythmia, they were unsure as to the underlying cause. Since his heart was enlarged and walls of his heart were thickened, they initially thought he had a pre-existing condition. A cardiac MRI and a nuclear cardiac scan were both performed without any definitive diagnosis. But a June 7 echo showed his heart had returned to normal size. His physicians then speculated Curtis had a genetic electrical issue in his heart, but that was not confirmed by a June 14 nuclear cardiac stress test, in which Curtis was injected with a radioactive tracer to show how the blood flows in his heart.
Curtis needed one more procedure – an implantable cardioverter defibrillator (ICD) to help monitor his heart for early signs of recurrence of potentially fatal arrhythmias and, if necessary, to shock it back to life. To implant the ICD, physicians used a dye to help them guide the wires to the right spot in the heart. Since the dye can damage weak kidneys, they had to wait until his kidneys were strong enough for the procedure.
Weaned from intermittent kidney dialysis, on June 20 Curtis was ready for the ICD procedure. To test the device and refine its settings, the doctors wanted to induce a cardiac arrest as part of the procedure. They backed off when they saw how anxious this plan made Curtis and Heather.
A day to remember: Curtis’s first day home from the hospital was also the start of the next stage of his recovery.
The ICD implant completed, Curtis finally could go home. It had been exactly four weeks since Curtis had crashed to the ground.
“This is absolutely the best outcome we could have ever asked for,” Heather wrote to friends and family on the patient web site, CaringBridge.org.
Curtis was back from the dead. But would he ever be back to normal?
VI. Ups and Downs
Curtis had come a long way, figuratively speaking, before he went home to East Bay. Muscle atrophy due to his weakened condition and spending so much time in his hospital bed had reduced his lean 178-pound frame by 30 pounds during his four weeks in the hospital. He had to learn to walk again. He had to regain his sense of balance, too. He started with a walker in the hospital, because weakness made even standing a chore. But he kept at it.
He took a combination of drugs and supplements: three drugs to keep down his blood pressure, another to reduce cholesterol, a drug to reduce mineral (phosphate) levels in his kidneys, a diuretic to reduce water retention, two drugs to thin his blood, an iron tablet, and calcium carbonate as needed for hiccups.
This drug “cocktail” needed constant adjustment in the first few months, with his doctors substituting some drugs and altering timing and dosage. The number of drugs to suppress his blood pressure was reduced when Curtis, who had low blood pressure already, complained they made him dizzy and breathless. He had to switch his cholesterol drug when the first gave him a full body rash and joint and muscle aches.
Curtis's heart got stronger, and he was able to regain weight, get back to taking long walks and even spinning on his stationary bike.
But his heart was getting stronger. He regained weight. He got back to his long walks and light workouts. He started spinning on his stationary bike. His visits to the doctor went from every week, to every month, to every six months.
To be sure, there were some nagging issues. He was sensitive to glare and sunlight, which could make him dizzy and uncomfortable. He had to wear polarized sunglasses, even at home where they had lots of windows. He often felt worn out and weak. Even going from sitting to standing or lying down to sitting could bring on disorientation and dizziness. He had a couple of blackouts in the first few months.
Yet given what had almost happened, he was feeling pretty good. He was improving. He and Heather were getting ready to have a baby, with all the excitement and preparation needed for that.
He was even cleared to go back to work.
“It was a great feeling to move towards normalcy,” Curtis said.
The feeling didn’t last.
Heather had increasingly noticed that if it wasn’t on his calendar or if someone didn’t remind him, Curtis would forget appointments. That would never have happened to him before. She also noticed that he became irritable more easily than before.
But not until an incident at work did Curtis come to agree with Heather that something wasn’t right.
His business had been struggling. Besides Curtis being absent for so many months, it had suffered a significant setback when one of its biggest suppliers went bankrupt. Easing back to work, Curtis began to feel the same stress and anxiety he felt before his collapse.
Then one day, he became upset with the engineers he had been working with, criticizing actions they had taken. It turned out they had done precisely what Curtis had told them to do – he just didn’t remember telling them. Curtis realized there was something wrong with his recall, he was irritable. It was time for him to back off from work, at least for a while.
Curtis was determined to get better and he would let nothing get in the way of that goal, even his business. He followed his drug regimen – with the help of Heather. He ate well. He made his doctor’s appointments. He walked and worked out regularly, getting daily exercise that would help him improve his physical condition.
Yet he was still hit by spells during which he would become dizzy, disoriented and weak, and he would have to sit down. These spells seemed random, inexplicable.
“It was extremely frustrating,” Curtis said.
It all began to gnaw at him. He had led a healthy lifestyle and had been in much better shape than most others around him, including his two brothers. Yet it was his heart had failed, not theirs. It didn’t make sense. It wasn’t fair.
He felt angry, depressed. He became anxious that his heart would fail again.
He needed help.
Curtis saw a psychologist. He took medication for anxiety and depression. He talked with other survivors, including a man who collapsed much like Curtis had, except while jogging not biking. He learned it was common for survivors of major heart incidents to suffer from depression and anxiety.
As he talked with the psychologist, Curtis saw that much of his frustration and disappointment came from falling short of his career expectations.
“I had pushed myself hard, exceptionally hard, the last four to five years before the incident,” he said.
Curtis was born and raised in the Bay Area. Like most Silicon Valley entrepreneurs, he had dreamed that his technology business would be a major success. He wanted the business to be a case study for others to follow.
“But the reality is, only a few succeed,” he said.
Curtis realized he simply could not take on the same level of responsibility and stress he had before. It was too much of a pressure cooker. He began to accept that not everyone meets all of their career goals – especially when they’re lucky just to be alive.
“I have accepted that things aren’t the same,” he said. “My new goals are more related to my wife, son, family and friends.”
CJ’s arrival changed everything for Curtis.
In January 2013, his son “CJ” – the baby he almost didn’t live to see – was born.
CJ was a life-changer for Curtis.
Playing with CJ or taking him for walks in his stroller, Curtis grew to love fatherhood. CJ was another reason to stay as healthy as possible and work his way back into optimal shape.
For Heather, seeing Curtis and CJ together was a dream come true. “I love when Curtis holds CJ in the air above his head and he’s wiggling and tickling him and CJ’s laughing,” she said.
“Having the chance to be with my son has been absolutely wonderful,” Curtis said.
Wonderful, but not always easy. Especially given the random nature of his side effects.
Late last fall, Curtis took CJ to play by a reservoir. On the way home, Curtis had taken CJ, who had fallen asleep in his car seat, with him to pick up some groceries. When Curtis returned to the car, he got dizzy and dropped the car seat with CJ onto the ground. That woke up CJ.
“He is screaming, I am sitting there, dizzy,” Curtis said. “It was just another in a series of constant reminders that the new normal is not the old normal and never will be.”
Fatherhood is a big part of Curtis’s “new normal.” The simple joys are precious, he says, such as the first time CJ said “Dada” or CJ trying to drag Curtis away from the dinner table to play.
But part of the new normal is fatherhood, which has its simple joys, such as the first time CJ said “dada” or CJ trying to drag Curtis away from the dinner table to play.
“Fatherhood is 90 percent awesome,” Curtis said. “I wish we had started having kids earlier.”
There are many things for which Curtis can be thankful, especially on that fateful day, Dr. Chang said. The “what ifs” are daunting. What if he had fallen when he was riding 30 miles per hour down the hill, as he had been doing minutes before he fell? What if he had collapsed in a remote area far from help, rather than in town near a fire station? What if there had not been a bystander who knew CPR? What if the hospital did not have the pump technology and staff to manage his critical condition?
“Now he has a cardiac implantable defibrillator to protect him against future events,” Dr. Chang said.
Curtis’s memory issues are subsiding. He has reset what is important to him and what he wants to get out of life. He is getting ready to go back to work – most likely with Heather.
He has even returned to biking.
It was a year to the day when Curtis got back up on his bike again. About 50 people – many old friends, but some new ones, such as Veronica, the ER nurse from John Muir – joined the ride. He might not be able to climb the steep hills like he did before but it felt good being back up on the bike again.
Curtis’s “new normal” does not mean a diminished life, he says. It means that his life took an entirely new direction, replete with blessings he had never dreamed of.
“I am very lucky to be alive.”
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1 Source: Reynolds HR, Hochman JS. Cardiogenic Shock: Current Concepts and Improving Outcomes. Circulation (2008); 117: 686-697. http://circ.ahajournals.org/content/117/5/686.full
2 AHA. http://www.heart.org/HEARTORG/Conditions/Arrhythmia/AboutArrhythmia/Ventricular-Fibrillation_UCM_324063_Article.jsp#
3 8.Hochman JS. Cardiogenic shock complicating acute myocardial infarction: expanding the paradigm. Circulation 2003;107:2998-3002
4 Source: http://www.uptodate.com/contents/prognosis-and-treatment-of-cardiogenic-shock-complicating-acute-myocardial-infarction
5 NHLBI http://www.nhlbi.nih.gov/health/health-topics/topics/shock/atrisk
6 Mayo Clinic definition: http://www.mayoclinic.org/diseases-conditions/cardiogenic-shock/basics/definition/con-20034247
7 Drugs.com http://www.drugs.com/pro/levophed.html
8 Cleveland Clinic. http://my.clevelandclinic.org/services/heart/disorders/heart-failure-what-is/ejectionfraction
9 CHI Health. http://www.chihealth.com/lvad-vad-impella
10 SCAI/ACC/HFSA/STS Clinical Expert Consensus Statement on the Use of Percutaneous Cardiac Assist Devices in Cardiovascular Care. http://www.scai.org/Press/detail.aspx?cid=91078003-f938-4133-854d-fdb1febcd1b8#.VSWfHnl0zX4
11 MedLine Plus. http://www.nlm.nih.gov/medlineplus/ency/article/003003.htm