Authors: James Forrester
Because of the valve system, blood flows continuously in only one direction (it “circulates”). It’s the same principle as the locks on the Panama Canal. When the inflow valves close, the outflow valves open. Like the needle of a metronome swinging back and forth, the two pairs of valves in the right and left heart open and close in perfect synchrony: the ticktock lasts a lifetime. And of course both the right and left hearts receive and eject blood through large vessels. The most important of these vessels is called the aorta, which delivers blood from the left ventricle to the entire body.
The muscle, valves, and electrical system do the work of the heart. Its fourth component, the coronary arteries, delivers oxygen-giving energy for all this hard work. The two coronary arteries, right and left, are the very first branches to come off the aorta; first dibs for life-sustaining oxygen goes to the body’s most important organ. The coronary arteries send branches that cover the entire surface of the heart and also plunge deep into the heart muscle so that no cell is deprived of oxygen.
When the aorta delivers blood into each organ, the red blood cell that transports the energy-giving oxygen changes in color from bright red to dark blue. Now it’s time to deliver the blood back to the lungs, add oxygen, and repeat the cycle. The blood from all the organs is collected in larger and larger veins and returned back to the right atrium where the process of reoxygenation begins anew. Arteries deliver blood; veins return it. It takes about sixty heartbeats to complete one cycle at rest.
The heart’s oxygen delivery system functions like a perfect machine because its form (anatomy) is so ingeniously integrated with its function. The muscular pump consists of collecting and pumping chambers. Circular flow is created by its system of one-way valves. The muscle meets its own intense need for an energy supply by first delivering oxygen to itself through its coronary arteries. And finally the whole system is exquisitely sensitive to the needs of its client, the body. Need more oxygen because you are in Yosemite, running from a black bear? No problem. Your heart can quintuple the flow of blood in seconds by tripling the heart rate and increasing the vigor of ventricular contraction.
Now that you know how your own heart actually works, let’s meet our first patient, who could one day be you.
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ALONE WITH HER
morning mug of coffee, Greta Adams stood on her patio trying to savor this daily solitary moment she cherished. Thirty-five years old, she loved the moist morning fog that rolled off the Pacific Ocean to be momentarily trapped in the hills above her home in Pacific Palisades, a small community northwest of Los Angeles. Each year nature repainted the canvas behind her, as the torrential rains and mudslides of February led to the explosion of yellow and purple mountain flowers of April, the now-green hills of June, and then finally the dry gray chaparral tumbling before the hot dry Santa Ana winds of September. How could anyone say California has no seasons?
This morning, though, the misty sea and mountain vista did not shake her free from a sense of foreboding. On most days her first thought was how to squeeze in an hour’s brisk walk and jog in nearby Will Rogers Park just north of Sunset Boulevard. But jogging, which had been her physical release, was now her bondage. Several weeks earlier she first noticed the discomfort, like a knot in her shoulder. At first, Greta was not so much concerned as she was puzzled. At first she thought it was a muscle cramp from climbing the rope that hung from a tree in her backyard. “I am young and I am healthy,” she reasoned. She had had her share of bumps and bruises over the years. Her thought seemed confirmed when she stopped her jog and the cramp rapidly disappeared. When it kept coming back on every morning run, she went to a massage therapist. Massage proved futile. When the knot extended to beneath her breastbone, she began to imagine more fanciful explanations. Could the moist salt air and the morning auto exhaust wafting over from Pacific Coast Highway cause chest pain? Could her discomfort be psychological, precipitated by her worry about a bully at Benjamin’s school? No, it wasn’t just in her mind, because the knot was now a small insolent fist, more insistent and more menacing with each run. It was time to see a doctor.
Greta and Tyler’s drive to my office took her east on Sunset Boulevard past colossal mansions worth tens of millions of dollars. Turning south in a few minutes, a massive eight-story, two-square-block, granite-brown building rose to dominate their view. Its central segment, crowned with a Star of David, stood astride the corner of Gracie Allen Drive and George Burns Road. The unusual street names bespoke a subtle reminder of the prodigious financial support given to Cedars-Sinai Medical Center by the tiny city that surrounds it. Walking the corridors to my fifth floor office, Greta and Tyler would discover that every public corridor is a museum of contemporary art, where huge Rauschenbergs compete with Warhol prints.
Greta made a gallant effort to smile brightly as she stood to greet me in my office, but the smile had already vanished before she spoke. As she sat she brushed a nonexistent hair from her forehead, then clasped her hands tightly in her lap. Greta was shouting fear and anxiety without speaking. So instead of talking about her symptoms, I started with family. I talked about my years coaching Little League, and moved on to ocean sports. Her son, Ben, was starting Little League and her husband Tyler was a surfer, she said, with a big smile. Now we were ready to talk about walks along the ocean and jogs in the hills.
I started with her history. Greta didn’t smoke, was still menstruating, and had no history of high blood pressure or diabetes. She had never had her blood lipids checked. Her father had died suddenly at age fifty-seven from a heart attack in the past year. Her mother was in good health; she had no siblings.
In diagnosing the cause of chest pain we begin with uncertainty. At one end of the spectrum Greta’s pain could be related to a psychological stress, such as her worry over her son. Or perhaps her father’s recent death from heart attack had caused her to obsess over her own risk. At the other end of the spectrum, coronary artery disease (CAD) might be the cause of her symptoms. I knew from large databases like the famous Framingham, Massachusetts, study that a thirtysomething-year-old woman with Greta’s demographics has less than 1% probability of having CAD. This woman also had chest pain, which increased the probability of disease, but by how much? In cardiology on most days, I find myself standing at the intersection of science and art, where objective probability meets subjective uncertainty.
I asked Greta about her chest pain. Angina, the pain caused by CAD, has three principal characteristics. Greta had all three. Her pain was located behind the sternum, brought on by exercise, and rapidly relieved by rest. The probability of CAD increases with the number of characteristics, and since she had all three, Greta had “typical angina.” If we examine all people with typical angina, 90% have coronary disease. For a young woman who begins with a less than 1% probability of disease, typical angina and a positive family history raises her probability of having coronary disease to about 50%.
I reached toward her and said, “Come, I’ll examine your heart.”
The hospital is elegant; the examining rooms are not. Greta glanced around the tiny six-by-eight-foot room with its spare undecorated white walls, resting her eyes on the narrow, lumpy three-piece examining table, with a step stool at its base. Her anxiety again filled the room as she sat with her legs dangling uncomfortably from the examining table. I started by resting both hands gently on her arm as I palpated her radial pulse. “Laying on of hands” speaks without words. It says I understand your unspoken anxiety. It recalls a parent’s touch that says, “I’m here to take care of you.” Greta’s pulses were all normal. By finding the tap of her heart on her chest wall, I determined that her heart size was normal. Listening with my stethoscope, I heard her heart valves closing normally, with no heart murmur and normal breathing sounds. With a normal heart size, no murmurs, and no evidence of heart failure, I was confident that congenital and valvular was not the cause of her pain and heart muscle disease was unlikely. That left the coronary arteries. Most people with undiagnosed CAD, like Greta, have a normal physical exam. Greta’s history and physical exam brought us face-to-face with the ultimate uncertainty, a 50/50 coin flip about CAD. So we would need a test.
Now I had choices. I could recommend either an exercise stress test, or even the definitive test, a coronary angiogram. Because an angiogram is expensive and invasive, I chose a stress test. There is no “right” choice, but this one cost a lot less, and it was immediately available.
The stress test was distinctly abnormal. In her brief visit, Greta’s probability of having CAD had skyrocketed from less than 1% to perhaps 90%. For Greta, a nagging unease over a morning cup of coffee was about to ramp up into a pounding anxiety, like a powerful migraine that obliterated every other thought. The diagnosis of CAD with its sinister implications would be a stunning, life-changing, shattering event.
CAD is due to deposits of fat in blood vessels (called plaques or atheromas). Large ones impede the blood flow particularly when the heart needs more oxygen during exercise or emotional stress. Like all muscles deprived of oxygen, the heart sends a pain signal to the brain. When the need for oxygen diminishes, the pain disappears. So, like Greta’s chest pain, typical angina is directly behind the chest, precipitated by stress, and disappears within a minute of termination of the stress. Atheromas create two life-threatening risks. They can cause abnormal heart rhythms, including ventricular fibrillation and sudden death. Rapid complete obstruction of a coronary artery by an atheroma causes heart muscle to die (a heart attack or myocardial infarction).
I was taught in medical school that people under thirty-five seldom contemplate their own mortality. Yet this would be Greta’s fate this afternoon. How do I tell a thirty-five-year-old mother that she has life-threatening disease that needs immediate attention, when she has never before been sick? I plodded back to talk with Greta, wondering how my sympathy could possibly match her struggle to absorb this personal tragedy. I stopped by the waiting room to ask Tyler to join me. He jumped to his feet with an expectant smile. We locked eyes; his smile vanished as I said simply, “Please join us.” As I ushered Tyler in ahead of me, I took a deep breath, and closed the door. I drew my chair from behind my desk to sit beside Greta and Tyler. “Greta,” I began, “let me show you what we found.” I showed them the ECG. I knew that neither was trained to interpret what they were looking at, but I felt Greta and Tyler needed assurance that specific, objective information provided a foundation for her diagnosis. Allowing Greta to focus on a piece of paper rather than blurting out the dreadful news directly could give her just a little more emotional space and time; a cushion, however small, for her psychic turmoil.
“What’s the next step?” she asked after they had seen the test results. My reply was shaped by uncertainty, cardiology’s loyal twenty-first-century companion. We had solved the uncertainty of Greta’s diagnosis, only to arrive at a new one. In Edgar Allan Poe’s famous 1843 Gothic short story “The Tell-Tale Heart,” a murderer is flummoxed by the sound of his dismembered victim’s heart that he imagines is still beating beneath the floorboards. Was Greta’s heart sending me a message of impending doom requiring immediate action, or did we have time to gradually implement treatment? Should Greta have immediate coronary angiography (X-ray pictures of her coronary arteries), or could she first have a trial of pills, say nitroglycerin, which reduces the pain of angina? I recalled nitroglycerin had relieved Willie’s symptoms, but it had not prevented his heart attack.
I gave Greta the argument favoring a trial of pills. Her angina was annoying but not disabling in her daily living. She still drove her car, shopped, cooked, and took care of Benjamin without episodes of angina. Her chest pain bothered her only on walk-jogs. She had not yet tried pills to alleviate the pain, but I felt the probability of pain relief with medication was quite high. Furthermore, I knew from randomized trials comparing medical therapy, angioplasty, and bypass surgery in patients with stable angina that, after five years of follow-up, there was no clear difference in survival among the choices. So one option was to initiate intensive medical therapy and closely monitor her response.
“For you, Greta,” I said, “there are two limitations to this choice. First, among those we start on medical therapy, about forty percent are not fully relieved of symptoms and end up going to angiography. More important, however, is that patients with accelerating symptoms of angina are at higher risk of heart attack than those with chronic stable angina. Your chest pain is very recent in onset and has progressed in both frequency and severity. So I cannot tell you that your angina is stable, and that means there is some increased risk for you to go home. There is only one certainty here; it is that there is no absolute best option.”
“What do you think I should do?” she whispered.
“This has to be your choice,” I replied. From our first days in medical school, we are admonished never to order, only to advise.
“But if I were in your situation, I would choose coronary angiography.” I paused to look directly at Tyler before returning to Greta. “Because your symptoms seem to be increasing, I’d have it now, Greta. I wouldn’t wait over the weekend.” The face of a friend who died suddenly on a Monday morning drive to the cath lab after he’d been sent home over a weekend with recent onset angina flashed in my mind. We sat in silence for a brief moment, then I rose to open my office door.
“Greta, the two of you need to have some time alone,” I said. I closed the door of my dimly lit office as I walked into the shimmering sunlight of a Los Angeles summer afternoon, knowing how at that moment how much each soul needed the other.
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GRETA’S STORY, AS
with all patients suspected of having CAD, spins off in a new direction with the decision for angiography, when the baton of patient responsibility is thrust into the hands of an interventional cardiologist in the catheterization laboratory. Jon Jackson is a superspecialist who spends his waking hours staring at a continuous X-ray image of his catheter and his patient’s heart. Like a concert pianist, he must continuously coordinate his foot, which controls the X-ray beam, the visual image from the monitor, and his hands advancing and rotating catheters, wires, and other devices. To be a great interventional cardiologist (one who performs catheterization laboratory procedures) requires the ability to imagine the third dimension of a two-dimensional X-ray image, consummate hand-eye coordination, clearheaded judgment, and the capacity to remain calm under extreme stress.