Sacha Bull

Surgery Insight: percutaneous treatment of prosthetic paravalvular leaks

Serious paravalvular leakage occurs in 1–5% of patients who have undergone surgical cardiac valve replacement procedures. Clinical manifestations include hemolysis, heart failure and arrhythmias. Presently, the gold standard treatment for severe paravalvular leakage is surgery; however, the outcomes remain far from optimum. In this Review we discuss the problem of paravalvular leak and focus on the role of percutaneous repair as a treatment option.

Myocardial steatosis and left ventricular contractile dysfunction in patients with severe aortic stenosis.

Background— Aortic stenosis (AS) leads to left ventricular (LV) hypertrophy and dysfunction. We hypothesized that cardiac steatosis is involved in the pathophysiology and also assessed whether it is reversible after aortic valve replacement. Methods and Results— Thirty-nine patients with severe AS (symptomatic=25, asymptomatic=14) with normal LV ejection fraction and no significant coronary artery disease and 20 age- and sex-matched healthy controls underwent cardiac 1H-magnetic resonance spectroscopy and imaging for the determination of steatosis (myocardial triglyceride content) and cardiac function, including circumferential strain (measured by magnetic resonance tagging). Strain was lower in both symptomatic and asymptomatic AS (−16.4±2.5% and −18.1±2.9%, respectively, versus controls −20.7±2.0%, both P<0.05). Myocardial steatosis was found in both symptomatic and asymptomatic patients with AS (0.89±0.42% in symptomatic AS; 0.75±0.36% in asymptomatic AS versus controls 0.45±0.17, both P<0.05). Importantly, multivariable analysis indicated that steatosis was an independent correlate of impaired LV strain. Spectroscopic measurements of myocardial triglyceride content correlated significantly with histological analysis of biopsies obtained during aortic valve replacement. At 8.0±2.1 months after aortic valve replacement, steatosis and strain had recovered toward normal. Conclusions— Pronounced myocardial steatosis is present in severe AS, regardless of symptoms, and is independently associated with the degree of LV strain impairment. Myocardial triglyceride content measured by magnetic resonance spectroscopy correlates with histological quantification. Steatosis and strain impairment are reversible after aortic valve replacement. Our findings suggest a novel pathophysiological mechanism in AS, myocardial steatosis, which may be amenable to treatment, thus potentially delaying onset of LV dysfunction.

A prospective, double-blind, randomized controlled trial of the angiotensin-converting enzyme inhibitor Ramipril In Aortic Stenosis (RIAS trial)

Aims Angiotensin-converting enzyme (ACE) inhibitors improve left ventricular (LV) remodelling and outcome in heart failure and hypertensive heart disease. They may be similarly beneficial in patients with aortic stenosis (AS), but historical safety concerns have limited their use, and no prospective clinical trials exist. Methods and results We conducted a prospective, randomized, double-blind, placebo-controlled trial in 100 patients with moderate or severe asymptomatic AS to examine the physiological effects of ramipril, particularly LV mass (LVM) regression. Subjects were randomized to ramipril 10 mg daily (n = 50) or placebo (n = 50) for 1 year, and underwent cardiac magnetic resonance, echocardiography, and exercise testing at 0, 6, and 12 months, with follow-up data available in 77 patients. There was a modest but progressive reduction in LVM (the primary end point) in the ramipril group vs. the placebo group (mean change −3.9 vs. +4.5 g, respectively, P = 0.0057). There were also trends towards improvements in myocardial physiology: the ramipril group showed preserved tissue Doppler systolic velocity compared with placebo (+0.0 vs. −0.5 cm/s, P = 0.04), and a slower rate of progression of the AS (valve area 0.0 cm2 in the ramipril group vs. −0.2 cm2 in the placebo arm, P = 0.067). There were no significant differences in major adverse cardiac events. Conclusion ACE inhibition leads to a modest, but progressive reduction in LVM in asymptomatic patients with moderate–severe AS compared with placebo, with trends towards improvements in myocardial physiology and slower progression of valvular stenosis. A larger clinical outcome trial to confirm these findings and explore their clinical relevance is required.

Cardiac toxicity screening by echocardiography in healthy volunteers: a study of the effects of diurnal variation and use of a core laboratory on the reproducibility of left ventricular function measurement.

Background: In investigational medicinal products testing centers (IMP), reliable methods for monitoring early signs of cardiotoxicity of a potential new drug in healthy volunteers are essential. This study examines what levels of left ventricular ejection fraction (LVEF) variance can be achieved with two‐dimensional echocardiography (2DE) in a core laboratory versus a site laboratory. Diurnal variability of LVEF and diastolic parameters were also reviewed. Methods and Results: 64 healthy males, (age range 18–40 years), with optimal echo windows were recruited. Two‐dimensional and tissue Doppler (TDI) echocardiography was performed by one dedicated sonographer using an Acuson Sequoia C256 machine. Heart rate and blood pressure were recorded simultaneously. Echocardiograms were performed at set time points (0, 1, 4, and 20 hours) on all subjects. The images were analyzed independently by one on‐site, unblinded, sonographer reader (site lab) and one experienced off‐site blinded physician over reader (core lab). The core lab showed significantly less variance in LVEF measurements than the site lab (5.5% vs. 19.9%). There was no significant diurnal variation in mean blood pressure, LVEF or E:A ratio measurements over 20 hours. Conclusions: The core lab had better reproducibility and significantly less variance in LVEF measurements by 2DE than the site lab. There was no diurnal variation in LV function measurement. (Echocardiography 2011;28:502‐507)

Acute Myocarditis Mimicking Reverse Takotsubo Cardiomyopathy

A 48 year-old man with type 1 diabetes mellitus was admitted to our hospital with diabetic ketoacidosis precipitated by a persistent 7-day febrile illness related to a viral upper respiratory infection. Two days after admission he had an episode of chest pain with a rise of troponin I up to 29 ng/mL but no ECG changes. Coronary angiography demonstrated minor plaque but no flow-limiting disease. Left ventriculography showed severe hypokinesis of basal and mid segments but preserved contractility of apical segments, consistent with a pattern of inverted Takotsubo cardiomyopathy (Figure 1A and 1D and online-only Data Supplement Movie I). The patient was then referred for cardiovascular magnetic resonance (CMR) imaging to determine the underlying cause of left ventricular impairment. Cine CMR imaging confirmed left ventricular wall …

Massive melanotic myocardial metastasis characterized by multiple cardiac imaging modalities

Melanoma has a great propensity for cardiac involvement but most cases are diagnosed post-mortem. We present the case of a 67-year-old man with history of malignant melanoma who presented with increasing dyspnea, fatigue and peripheral edema. A large myocardial metastasis was identified on transthoracic echocardiography, and further characterized with cardiovascular magnetic resonance prior to surgery.

Letter Regarding Article by Valgimigli et al, “Short- and Long-Term Clinical Outcome After Drug-Eluting Stent Implantation for the Percutaneous Treatment of Left Main Coronary Artery Disease”

To the Editor:nnShort- and long-term treatment with clopidogrel has been shown to be beneficial in patients with atherosclerosis, non-ST elevation and ST-elevation acute coronary syndromes, and those subsets undergoing percutaneous coronary intervention. Combined therapy reduces the rate of recurrent events, including myocardial infarction, repeat revascularization, and death, compared with therapy with aspirin alone.1–3nnIn their article, Valgimigli et al describe the benefits of drug-eluting stents (DESs) versus bare-metal stents (BMSs) in patients with left main stem disease. Part of this benefit is a reduction in the rate of myocardial infarction, as well as the subsequent need for target-vessel revacularization.4 Roughly 50% of the patients in the DES and BMS groups …