A 70-year-old man presents to his primary care physician with worsening shortness of breath on minimal exertion over the past 6 months. He has a history of coronary artery disease and severe mitral valve regurgitation, which had been treated with coronary bypass grafting and mechanical mitral valve replacement 6 years earlier. He has permanent atrial fibrillation. His cardiac risk factors include type 2 ­diabetes mellitus, obesity, hypertension, and prior nicotine dependence (quit smoking 10 years ago after a 30-pack-year history).

Due to his multiple morbidities, the differential diagnosis is broad. A thorough assessment of the patient’s history and physical exam, however, can often appropriately direct the evaluation.

On further questioning, the patient describes a gradual onset of his shortness of breath; currently, he cannot master 1 flight of stairs without getting severe symptoms (New York Heart Association class III). He denies typical chest pain, palpitations, fever, or chills. Since cardiac rehabilitation after his open-heart surgery, he has not performed regular exercise.

On physical exam, his vital signs are within normal limits (blood pressure 135/75 mm Hg, heart rate 75 bpm [irregularly irregular], respiratory rate 14 breaths/min, normal temperature). The most pertinent positive finding on his physical exam is a 3/6 harsh, medium-pitched, holosystolic murmur, which is best heard at the apex and the upper left sternal border. He has mild to moderate bibasilar crackles on posterior pulmonary auscultation and +1 to 2 pretibial edema. His jugular venous pressure is elevated to the mid-neck (5 cm above the jugulum, corresponding to 7-8 mm Hg assumed central venous pressure). His laboratory workup is unremarkable, with a normal complete blood count and metabolic panel and a hemoglobin A1c of 7%.

He is on a stable medical regimen that includes aspirin, ­furosemide, β-blocker therapy, and an oral antidiabetic.

After this initial assessment, his differential diagnoses are as follows:

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  Progressive coronary artery disease; his shortness of breath could represent an angina equivalent in the setting of diabetes mellitus.

  
  
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  Severe physical deconditioning in the setting of morbid obesity.

  
  
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  Mitral valve regurgitation (ie, failing mitral valve prosthesis leading to either transvalvular or paravalvular regurgitation).

  
  
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  Pulmonary disease such as chronic obstructive pulmonary ­disease/emphysema; he has a long history of smoking.

  
  
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  Diastolic dysfunction associated with atrial fibrillation and ­episodes of poor rate control could contribute to his shortness of breath.

In a patient who has a history of mitral valve replacement who presents with increasing shortness of breath and a loud holosystolic murmur, a transthoracic echocardiogram will be key in the initial workup. The echocardiogram provides the primary care physician and cardiologist with valuable information on the patient’s left and right ventricular systolic function, diastolic function, noninvasive assessment of pulmonary pressures, and valvular function. If the transthoracic echocardiogram does not reveal any significant pathology, further workup may include stress testing and pulmonary function testing.

The patient’s transthoracic echocardiogram showed preserved left ventricular function (ejection fraction 50%) and normal right ventricular function. There was mild to moderate tricuspid valve regurgitation with an estimated right ventricular systolic pressure of >60 mm Hg (suggesting severe pulmonary hypertension). The left atrium was severely enlarged. Due to shadowing behind the mechanical mitral valve prosthesis, only the apical 4-chamber view revealed a color Doppler jet of moderate to severe mitral valve regurgitation, which appeared to be paravalvular (Figure 27-1).

Assessment of metallic mitral valve prostheses can be difficult due to shadowing from the prosthesis into the left atrium, which can obscure the regurgitation signal. A thorough Doppler assessment, however, can help confirm regurgitation as the major culprit. Our patient had an E velocity of 2.7 m/s, a tissue Doppler ratio (mitral valve time-velocity integral [TVI]/left ventricular outflow tract TVI) of 3.4, and pressure half-time of 126 milliseconds, indeed suggesting regurgitation as the major culprit.¹

The transthoracic echocardiogram, therefore, established the likely cause of the patient’s increasing shortness of breath: a significant paravalvular leak medial to his mitral valve prosthesis.

Paravalvular regurgitation affects 2% to 17% of all surgically implanted prosthetic heart valves, with an estimated 500 to 10,000 cases annually.^2,3 The most common etiologies for paravalvular regurgitation are tissue friability, annular calcification, and infection; patients can present with symptoms of congestive heart failure, hemolytic anemia, or both.

If the paravalvular leak is severe and aggressive medical ­management fails, there are 2 management options: (1) surgical reoperation, which usually carries a significant mortality risk, or (2) a percutaneous closure of the paravalvular leak.

Due to the increased morbidity and mortality, reoperation is often best avoided, especially if the underlying paravalvular tissue is friable or heavily calcified. Medical therapy (including standard heart failure management and repeated blood transfusions) can help with symptoms but will not prevent progressive heart failure from volume and/or pressure overload or prevent the need for frequent administration of blood products.

Our patient was subsequently seen by cardiovascular surgery and felt to be too high risk for reoperation.

The next step in the workup should include a transesophageal echocardiogram (TEE). The advantage of this approach is less shadowing of the mitral valve prosthesis and thus a more defined view of the location and approachability of the paravalvular leak. The 2-­dimensional echocardiogram is routinely combined with 3-­dimensional (3D) imaging, which further facilitates procedural planning.

Our patient’s TEE showed a large anteromedial paravalvular leak with severe paravalvular regurgitation (Figure 27-2).