Cardiovascular Imaging in Infective Endocarditis: A Multimodality Approach.

Multimodality imaging plays a pivotal role in the evaluation and management of infective endocarditis (IE)-a condition with high morbidity and mortality. The diagnosis of IE is primarily based on the modified Duke criteria with echocardiography as the first-line imaging modality. Both transthoracic and transesophageal echocardiography delineate vegetation location and size, assess for paravalvular extension of infection, and have the added advantage of defining the hemodynamic effects of valvular or device infection. Native and prosthetic valve IE, infections relating to cardiac implantable electronic devices, and indwelling catheters are effectively evaluated with echocardiography. However, complementary imaging is occasionally required when there remains diagnostic uncertainty following transesophageal echocardiography. Multidetector computed tomography and nuclear imaging techniques such as positron emission tomography and white blood cell scintigraphy have been shown to reduce the rate of misdiagnosed IE particularly in the setting of prosthetic valve endocarditis, paravalvular extension of infection, and cardiac implantable electronic devices. In this review, we describe a modern approach to cardiac imaging in native and prosthetic valve endocarditis, as well as cardiac implantable electronic devices including pacing devices and left ventricular assist devices. Current guidelines addressing the role of multimodality imaging in IE are discussed. The utility of imaging in the assessment of local and distant endocarditis complications such as pericardial sequelae, myocarditis, and embolic events is also addressed.

Ranolazine in Symptomatic Diabetic Patients Without Obstructive Coronary Artery Disease: Impact on Microvascular and Diastolic Function.

BACKGROUND: Treatments for patients with myocardial ischemia in the absence of angiographic obstructive coronary artery disease are limited. In these patients, particularly those with diabetes mellitus, diffuse coronary atherosclerosis and microvascular dysfunction is a common phenotype and may be accompanied by diastolic dysfunction. Our primary aim was to determine whether ranolazine would quantitatively improve exercise-stimulated myocardial blood flow and cardiac function in symptomatic diabetic patients without obstructive coronary artery disease. METHODS AND RESULTS: We conducted a double-blinded crossover trial with 1:1 random allocation to the order of ranolazine and placebo. At baseline and after each 4-week treatment arm, left ventricular myocardial blood flow and coronary flow reserve (CFR; primary end point) were measured at rest and after supine bicycle exercise using 13N-ammonia myocardial perfusion positron emission tomography. Resting echocardiography was also performed. Multilevel mixed-effects linear regression was used to determine treatment effects. Thirty-five patients met criteria for inclusion. Ranolazine did not significantly alter rest or postexercise left ventricular myocardial blood flow or CFR. However, patients with lower baseline CFR were more likely to experience improvement in CFR with ranolazine (r=-0.401, P=0.02) than with placebo (r=-0.188, P=0.28). In addition, ranolazine was associated with an improvement in E/septal e' (P=0.001) and E/lateral e' (P=0.01). CONCLUSIONS: In symptomatic diabetic patients without obstructive coronary artery disease, ranolazine did not change exercise-stimulated myocardial blood flow or CFR but did modestly improve diastolic function. Patients with more severe baseline impairment in CFR may derive more benefit from ranolazine. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01754259.

Serum Amyloid P-Component Prevents Cardiac Remodeling in Hypertensive Heart Disease.

The potential for serum amyloid P-component (SAP) to prevent cardiac remodeling and identify worsening diastolic dysfunction (DD) was investigated. The anti-fibrotic potential of SAP was tested in an animal model of hypertensive heart disease (spontaneously hypertensive rats treated with SAP [SHR - SAP] × 12 weeks). Biomarker analysis included a prospective study of 60 patients with asymptomatic progressive DD. Compared with vehicle-treated Wistar-Kyoto rats (WKY-V), the vehicle-treated SHRs (SHR-V) exhibited significant increases in left ventricular mass, perivascular collagen, cardiomyocyte size, and macrophage infiltration. SAP administration was associated with significantly lower left ventricular mass (p < 0.01), perivascular collagen (p < 0.01), and cardiomyocyte size (p < 0.01). Macrophage infiltration was significantly attenuated in the SHR-SAP group. Biomarker analysis showed significant decreases in SAP concentration over time in patients with progressive DD (p < 0.05). Our results indicate that SAP prevents cardiac remodeling by inhibiting recruitment of pro-fibrotic macrophages and that depleted SAP levels identify patients with advancing DD suggesting a role for SAP therapy.

Natural history, management, and outcomes of peripartum cardiomyopathy: an Irish single-center cohort study.

AIM: To describe the natural history, management and outcomes of peripartum cardiomyopathy (PPCM) in an unselected Northern European population. METHODS: A retrospective single-center observational study was performed at a tertiary referral heart failure and transplantation unit. Outcomes measured were baseline demographics, clinical presentation, course, and treatment. Echocardiographic findings were compared at baseline, 2 months, and 6 months. RESULTS: Twelve cases of PPCM were identified between 2002 and 2008. Mean age was 34.7 years. Nine patients were multiparous and nine had preeclampsia. Ten patients presented in the first week postpartum. Two patients required inotropic support. Mean ejection fraction (EF) at presentation was 27% (SD = 8%) which improved to 47% (SD = 13%) at 6 months. At this time, 10 patients were asymptomatic and 6 had recovered normal cardiac function. Left ventricular (LV) function improved but did not reach normal limits in five cases. One case with persistent severe LV dysfunction required cardiac transplantation. One patient suffered an arrhythmic death several years after the 6 months follow-up period. CONCLUSIONS: PPCM is a rare condition. With appropriate therapy, a good clinical outcome is common but not universal. Continued deterioration requiring ventricular support and cardiac transplantation can occur. In our cohort, older maternal age, multiparity, and preeclampsia appeared to be risk factors.

Steady-state free-precession (SSFP) cine MRI in distinguishing normal and bicuspid aortic valves.

PURPOSE: To assess the diagnostic sensitivity and specificity of double-oblique true fast imaging with steady-state precession (SSFP) cine MRI in distinguishing normal and bicuspid aortic valves. MATERIALS AND METHODS: Echocardiograms on patients referred for MRI of the heart and thoracic aorta over a four-year period were reviewed retrospectively. A total of 17 patients with bicuspid aortic valve were identified and compared to 21 randomly chosen control patients. All patients had double-oblique SSFP (True FISP) cine MRI of the aortic valve independently assessed by two radiologists in a blinded fashion, and graded as bicuspid or normal. Image quality was graded as 1, 2, or 3. Discordance was resolved by consensus. RESULTS: A total of 38 cases were reviewed (27 men, 11 women; age range = 15-67 years, mean = 25.33 years). Interobserver agreement was 0.97 (36/38 cases). One case of normal tricuspid valve was reported as bicuspid by both readers (false-positive). All cases in which disparity arose were rated suboptimal by both readers (grade 2 or 3). Consensus review yielded sensitivity = 100%, specificity = 95.2%, positive predictive value = 94.4%, and negative predictive value = 100%; overall diagnostic accuracy was 97.36%. Interobserver agreement was 0.97. CONCLUSION: Double-oblique True FISP cine MR imaging of the aortic valve is 100% sensitive and 95% specific in distinguishing normal and bicuspid aortic valves.