Citations

The percutaneous Melody valve is occasionally used for the treatment of bioprosthetic valve dysfunction and is an attractive option for patients at high risk for repeat operation. Anticoagulation is not routinely recommended following Melody valve placement. We present the case of a young woman who developed subacute spontaneous thrombosis of her Melody valve 15 months after placement. Her clinical status was compromised by severe tricuspid prosthesis stenosis and right-to-left shunting across a small residual atrial septal defect. Surgical replacement was required. To our knowledge, this is the first reported case of spontaneous thrombosis of a Melody valve in the tricuspid position.

Background— Low-flow, low-gradient aortic stenosis (AS), associated with a poor prognosis, can be caused by a reduced stroke volume despite a preserved ejection fraction (left ventricular ejection fraction). We hypothesized that impaired ventricular diastolic filling secondary to constrictive pericarditis (CP) could contribute to reduced transaortic gradients in patients with AS+CP. We sought to examine the characteristics and outcomes of this unique cohort. Methods and Results— We analyzed 84 patients with different degrees of AS and preserved left ventricular ejection fraction (≥50%): 28 diagnosed with concomitant CP by echocardiography and 56 patients without CP matched by age, sex, and AS severity during 1998 to 2013. Prior mediastinal radiation (32.1% versus 5.4%; P =0.0072) and cardiac surgery (50.0% versus 3.6%; P =0.0016) were more common in AS+CP patients than those with AS only. AS+CP patients had lower left ventricular stroke volume index and mean transaortic gradients. Five-year survival was 34.3% for AS+CP patients and 89.1% for those with AS only ( P <0.001). In univariate analysis, prior mediastinal radiation (hazard ratio, 8.35; 95% confidence interval, 3.38–20.62; P <0.001), reduced left ventricular stroke volume index of <35 mL/m 2 (hazard ratio, 12.52; 95% confidence interval, 3.97–39.48; P <0.001), and concomitant CP (hazard ratio, 13.65; 95% confidence interval, 4.85–38.41; P <0.001) were highly associated with increased mortality. Conclusions— Our findings highlighted the possibility of CP as a pathophysiological mechanism for low-flow, low-gradient AS. Left ventricular stroke volume index and transaortic gradients were commonly reduced in AS in the setting of CP despite a preserved left ventricular ejection fraction, which may result in underestimation of AS severity. Prior mediastinal radiation, lower left ventricular stroke volume index, and concomitant CP were associated with poorer survival in AS patients.

ObjectivesPrior analysis at our institution found that patients with hypertrophic cardiomyopathy (HCM) who experience postprandial symptoms (PPS) are more likely to have resting left ventricular outflow tract (LVOT) obstruction and reduced quality of life. Our objective was to determine whether PPS in patients with HCM vs healthy subjects occur as a result of measurable hemodynamic alterations in the postprandial hemodynamic response.MethodsWe conducted a prospective cross‐sectional study examining 45 patients with HCM and 10 controls who underwent fasting and postprandial 2‐dimensional Doppler echocardiography. Postprandial echocardiographic measurements were obtained at symptom onset or 30 minutes after consumption of a standardized meal, whichever occurred first.ResultsThe HCM population included 18 (40%) patients with PPS and 27 (60%) without PPS. Compared to controls, mean resting peak LVOT gradient was 23.4 ± 17.6 mmHg in HCM patients with PPS and 25.1 ± 33.1 mmHg in those without PPS (P = 0.10). The mean change in peak LVOT gradient after a meal was 0.7 ± 1.1 mmHg for controls, 5.0 ± 8.3 mmHg for HCM patients with PPS, and 1.5 ± 18.2 mmHg for HCM patients without PPS (P = 0.64).ConclusionAlthough the ability to provoke an increased LVOT gradient with a postprandial, upright exercise study protocol was recently reported, the current study suggests that a resting, supine, postprandial protocol does not elicit evidence of LVOT obstruction. Therefore, future investigations should consider whether simply performing an upright postprandial study in HCM patients with PPS will provide evidence of dynamic LVOT or if the addition of an exercise component is necessary.

NISHIMURA, R.A. et al.: Hemodynamic and symptomatic consequences of ventricular pacing. After implantation of a ventricular demand pacemaker (VVI), occasional patients continue to have dizziness, syncope, or near syncope (“pacemaker syndrome”). To identify patients in whom VVI pacing may have deleterious effects, we compared cuff blood pressure responses to VVI pacing with blood pressure responses to atrioventricsler sequential pacing (DVI) or sinus rhythm in 50 consecutive patients. Patients with intact ventriculoatrial conduction had a much greater decrease in systolic blood pressure with VVI pacing (24 ± 11 mm Hg) than those with ventriculoatrial dissociation (−4 ± 15 mm Hg) (P<0.005). Patients who were in heart failure had a lesser decrease in blood pressure with VVI pacing than did those without failure (P<0.05); 13 of the 14 heart failure patients lacked ventriculoatrial conduction. Ten patients had symptomatic dizziness after VVI pacing; the incidence of symptoms was higher in patients with ventriculoatrial conduction (9 of 23) than in those without ventriculoatrial conduction (1 of 27) (P<0.003). We conclude that the presence of intact ventriculoatrial conduction appears to be a crucial determinent of the hemodynamic response to VVI pacing, and its presence may identify patients who are at risk for “pacemaker syndrome.”

A 33-year-old male with systemic lupus erythematosus (SLE) presented with acute abdominal pain and was found to have lupus mesenteric vasculitis on imaging and during exploratory laparotomy. Post laparotomy he continued to have persistent nausea and dyspepsia and an electrocardiogram showed evidence of an inferior ST elevation myocardial infarction (STEMI). Emergency cardiac catheterization showed evidence of thrombotic right coronary artery occlusion. His coronaries were otherwise normal with no evidence of underlying coronary artery disease. Extensive workup with trans-esophageal echo, serologies for antiphospholipid antibody syndrome (APS) and bubble study was negative. This effectively ruled out Libman–Sacks endocarditis, APS-induced arterial thrombus and paradoxical emboli as potential causes of his STEMI. By exclusion of other causes, the etiology of his STEMI was felt to be secondary to in-situ coronary artery thrombosis in the setting of active SLE. To the best of our knowledge, this is the first report of a patient with SLE presenting with both lupus mesenteric vasculitis and in-situ coronary arterial thrombosis in the absence of APS.

In this report, we describe the case of a 41‐year‐old man with hypertrophic cardiomyopathy presenting with right‐sided congestive heart failure symptoms. Noninvasive testing was suggestive, but non‐diagnostic for constrictive pericarditis (CP) and thus invasive hemodynamic catheterization was performed. The unique presence of both hypertrophic cardiomyopathy and constriction in this case led to lack of “modern” echocardiographic and invasive criteria for CP, based upon findings of enhanced ventricular dependence. However, classic hemodynamic criteria of early rapid filling with elevation and end‐equalization of diastolic pressures were present, and the patient ultimately received pericardiectomy with dramatic clinical improvement. © 2015 Wiley Periodicals, Inc.

Confirmation of the presence and magnitude of left ventricular outflow tract (LVOT) obstruction is a critical component of the evaluation of symptoms in patients with hypertrophic cardiomyopathy (HCM). The presence of LVOT obstruction in patients with severe symptoms refractory to pharmacologic therapy identifies a subgroup of HCM patients who may benefit from septal reduction therapy. Two‐dimensional echocardiography with continuous wave Doppler is the main tool for confirming the presence and severity of LVOT obstruction in HCM. However, when uncertainty remains following non‐invasive evaluation, invasive hemodynamics studies are required to confirm and quantify LVOT obstruction. In this manuscript we describe a series of 6 cases in which hemodynamic catheterization is instrumental in supplementing non‐invasive imaging in the assessment of LVOT obstruction in HCM. © 2015 Wiley Periodicals, Inc.