Case Study: Undiagnosed Endocarditis On An Artificial Heart Valve

The Error, Stated Plainly

On the first night, someone got it right.

A man in his late fifties came into a Pennsylvania emergency department with a high fever, chest pain, and a urinary infection that oral antibiotics had not touched. He was admitted. The physician who examined him listened to his chest and heard the mechanical click of an artificial heart valve, one that had been implanted only about four months earlier. In the admission note, that physician wrote down the possibility that mattered most. Infection of the mechanical aortic valve. IV antibiotics were started and cardiology was asked to evaluate him for a transesophageal echocardiogram, which is the specialized ultrasound that can actually see an infection growing on prosthetic valve hardware.

The test was never done.

Over the next several days his blood cultures grew bacteria. He went to the intensive care unit in septic shock. His white blood cell count nearly doubled. He spiked fevers. His blood pressure dropped. And on the morning of his discharge, hypotensive, tachycardic, and with a white count that had not come down and had shifted sharply toward active bacterial infection, he was sent home.

Roughly two weeks later he died on an operating table, his aortic valve and the surrounding heart tissue destroyed by an infection that had been growing, unchecked and undiagnosed, the entire time.

Why a Four Month Old Valve Changes Everything

Endocarditis is an infection of the inner lining of the heart and its valves. When it develops on an artificial valve it is called prosthetic valve endocarditis, and it does not behave like an infection on a native valve.

Bacteria form a colony, called a vegetation, on the artificial material. That material has no blood supply of its own, so the body’s immune cells and circulating antibiotics reach it poorly. The colony keeps growing and destroying tissue even while antibiotics quiet the patient’s outward symptoms. Left alone, the infection burrows out from the valve into the surrounding heart tissue, forming abscesses, tearing open channels between chambers, and loosening the valve from its seat. Once it gets that far, antibiotics alone cannot cure it. It takes surgery to remove the infected hardware and rebuild what the infection has eaten away, and the risk of that operation climbs steeply the longer the infection has been allowed to run.

The single most important variable in this case was how recently the valve had been implanted. A newly placed prosthetic valve is not immediately covered by the body’s own endothelial lining. That process takes roughly six months. Until it finishes, the artificial surface is exposed, and bacteria circulating in the bloodstream stick to it far more readily than they would to a fully healed valve. A patient with bacteria in his blood and a valve implanted within the previous several months is, by definition, in the highest risk window there is.

This patient had a congenital aortic valve abnormality that had narrowed and stiffened his valve over decades until surgeons replaced it with a mechanical one. He also had diabetes and several other chronic conditions common in middle age. About four months after the valve surgery he developed urinary symptoms, was treated for a urinary tract infection with an oral antibiotic, did not improve, ran fevers at home for days, and then developed chest pain.

So the physician on the first night was right to suspect what he suspected. The question the case turned on is why the plan he wrote down was abandoned.

How the Right Diagnosis Got Talked Out of the Chart

The blood cultures grew an organism that physicians usually associate with urinary tract infections rather than with heart valves. The infectious disease consultant seized on that. The documented reasoning was that a transesophageal echocardiogram was unnecessary, because that class of bacteria rarely seeds prosthetic material. Cardiology agreed. The admitting physician’s original plan was quietly dropped.

Instead, the team did a transthoracic echocardiogram, which is the ultrasound performed from outside the chest. It showed no visible vegetation. At that point the possibility of valve infection was treated as closed.

Where Our Firm Came In

In the months after his death, the family got no meaningful explanation from the hospital. What they had were discharge summaries, operative notes, and echocardiogram reports written in a language none of them could read. What they did not have was an answer to the only question that mattered, which was whether he had to die.

The firm obtained the complete records of both hospitalizations along with the outpatient records that preceded them, and, critically, the primary imaging data from every echocardiogram, not just the reports describing them. That distinction matters more than most people realize. A cardiology report is not the study. It is one physician’s written account of what that physician noticed and chose to record on the day it was read. When a case turns on a subtle finding, the only way to know what was actually on the images is to have qualified experts read the underlying data themselves.

Experts were retained in infectious disease medicine, in cardiology and echocardiography, and in hospital medicine. Their conclusions converged.

Three Errors in the Reasoning That Closed the Door

Unlikely is not impossible. The organism in question is an uncommon cause of prosthetic valve endocarditis. But uncommon describes a population, not a patient. This patient had documented bacteria in his bloodstream and a mechanical valve implanted inside the endothelialization window. The infectious disease expert’s opinion was that the consultant did not appear to appreciate the significance of that timing, and that the statistical rarity of the organism could not carry the weight the team put on it.

The fever never fit the diagnosis they had given it. A fever that high is not what an uncomplicated bladder infection produces. A kidney infection could produce it, but the testing pointed away from that. The urinalysis showed very few white cells and few organisms. The standard screening chemistries were negative. The urine stayed concentrated, which the kidneys lose the ability to do in a significant kidney infection. Imaging of the kidneys was normal. And in a diabetic patient, an infection severe enough to drive a fever of that size would be expected to produce some measurable kidney dysfunction, and there was none. The team was left holding a working diagnosis that could not account for how sick the patient actually was. Instead of asking what else could explain it, they stopped looking.

They relied on a test that could not answer the question. A transthoracic echocardiogram is performed from outside the body, so its sound waves have to travel through the chest wall, the ribs, and lung tissue before they reach the valve. Artificial valve hardware makes that worse, because prosthetic material reflects and scatters ultrasound and casts acoustic shadows across exactly the region where a vegetation or an abscess around the valve would form. A transesophageal study avoids both problems by putting the probe in the esophagus, directly behind the heart, and it is substantially more sensitive for infection involving prosthetic hardware. That is why published guidance on infective endocarditis directs clinicians to go on to a transesophageal study when prosthetic valve infection is suspected, including when a transthoracic study has already come back negative. A negative transthoracic study in a patient like this one ruled out very little. It was treated as though it ruled out everything.

The Day the Case Turned On

The patient improved on IV antibiotics for a few days and the plan became discharge. Then everything reversed. His white blood cell count nearly doubled and shifted sharply toward the immature forms that signal active bacterial infection. His temperature climbed. His heart rate rose. By the next morning his blood pressure had fallen into a range that signals shock. He was discharged that morning anyway.

The firm’s cardiology expert went back to the raw echocardiogram data rather than the reports. On the earlier study he identified a subtle focal thickening on the valve prosthesis with a rarefied center, a finding potentially consistent with an early abscess.

What made that opinion credible is what the expert conceded. Read in isolation on the day it was performed, he said, that finding was not necessarily abnormal, and he would not criticize a physician for passing over it. But read again in light of a patient who remained febrile, tachycardic, hypotensive, and profoundly leukocytic days into treatment, it demanded a transesophageal echocardiogram.

His opinion was that nobody reassessed the existing imaging or ordered additional testing when the clinical picture fell apart, and that discharging a patient admitted with severe sepsis on that day, with those vital signs and that white count, did not meet the standard of care. That window was the last realistic chance to change the outcome.

Follow up blood cultures should also have been drawn during the fever spike. The infectious disease expert’s opinion was that they would have been positive, that a transesophageal study at that point would have found the valve infection, and that if the diagnosis had been made during the first admission and appropriate surgery performed, the patient more likely than not would have survived. The best odds belonged to the earliest intervention, because valve destruction in endocarditis progresses relentlessly even while antibiotics mute the outward signs.

The Second Admission, and the Comparison Nobody Made

He came back days after discharge, short of breath, in congestive heart failure, with a laboratory marker of heart muscle injury elevated. A limited echocardiogram was read as essentially normal.

The firm’s cardiology expert re-reviewed that study and found what the interpreting cardiologist had not reported. The shape of the heart had changed. A large clear space had appeared in the wall between the chambers. Doppler imaging showed flow through it, consistent with an abnormal channel forming in precisely the area flagged on the earlier study. There was a new leak around the valve, a new fluid collection around the heart, worsening leakage at a second valve, and clear evidence of heart failure. The prosthesis itself was no longer seated securely.

The most important point was that the physician reading that study never compared it to the earlier one. The study had been ordered as a limited examination rather than a comprehensive one, and the expert addressed that directly. A narrower scope does not relieve the physician reading the study of the obligation to look at what came before. A prosthetic valve has no universal normal. Expected findings vary with the type of valve, its size, and the individual patient, which is why published echocardiography guidance calls for a baseline study after implantation and for later studies to be read against it. A prior study is the only meaningful reference point there is. In a patient with a mechanical valve, recently discharged from an admission for sepsis, with a study already on file, the expert’s opinion was that comparison was required, that an interpretation made without it was incomplete, and that it fell below the standard of care.

The diagnosis was finally made the next day, when an adequate transesophageal echocardiogram showed a large vegetation attached to the mechanical valve, moving with every heartbeat, and an abscess that had extended from the valve into the surrounding structures of the heart.

Then several more days passed. The infectious disease expert reviewed that stretch of the chart, meaning a patient with a confirmed, actively destroying valve infection lying in a hospital bed receiving antibiotics and heart failure treatment, and concluded that the delay was unexplained and unjustifiable. A first surgical attempt had to be aborted when the patient developed sudden pulmonary edema on the table. When the operation finally went forward, surgeons found extensive abscess and tissue destruction requiring replacement of more than one valve and reconstruction of the surrounding tissue. His heart could not be weaned from the bypass machine. He died that day.

How the Matter Was Resolved

The matter resolved through a confidential settlement without a trial, which spared the family years of litigation and the ordeal of testifying about the worst weeks of their lives.

What This Case Teaches

A diagnosis written in an admission note is only as good as the follow through. The correct suspicion was recorded on the first night by the first physician to examine him. What failed afterward was not recognition. It was the workup.

Statistics describe populations, not the patient in the bed. An organism that rarely seeds prosthetic valves still seeds them sometimes, and a valve implanted inside the endothelialization window is the setting where it happens.

A negative test only means something if the test could have found the thing. A transthoracic echocardiogram is not a rule out study for infection on prosthetic hardware, and treating it as one is how this diagnosis gets missed.

Reports are not studies. Two of the most important findings in this case were sitting in imaging data that had already been performed, interpreted, and filed away. They were found because someone qualified went back and looked at the images themselves.

A new study should be read against the old one. For a prosthetic valve there is no universal normal, so the prior study is the reference point. A limited examination does not change that.

How Lupetin & Unatin Helps Families After a Missed or Delayed Diagnosis

Delayed diagnosis cases are hard to prove, and they are a substantial part of our practice. The patient was already sick, so the hospital’s defense writes itself. He had a serious illness, we treated him, he did not survive. Proving otherwise means identifying the specific point at which reasonable physicians would have done something different, and then proving that doing it would have changed the outcome. Both halves are necessary, and in nearly every medical case each of them has to be supported by qualified expert testimony.

In cases like this one, that work means getting every page from every provider, going back years when the history requires it. It means going past the reports to the underlying images and data and having our own experts read them independently. It means retaining specialists in each discipline the case touches, and doing it early, before positions harden.

If someone you love was seriously injured or died after an infection, a heart condition, or another dangerous diagnosis was missed or delayed, particularly after being sent home from a hospital while still visibly ill, you are entitled to find out whether the standard of care was met. The medical records alone will usually not tell you.

Lupetin & Unatin represents families throughout Pennsylvania in medical malpractice matters. Consultations are free and confidential. We handle these cases on a contingency fee basis, which means our attorney’s fee is a percentage of any recovery and no fee is charged if there is no recovery. We advance the costs of investigating and litigating a case, and depending on the terms of the fee agreement and the outcome, a client may remain responsible for costs and expenses. Pennsylvania’s deadlines for filing these claims are strict and can be shorter than people expect.