Percutaneous patent foramen ovale closure: outcomes with the Premere and Amplatzer devices.

BACKGROUND: Transcatheter closure of patent foramen ovale (PFO) has rapidly evolved as the preferred management strategy for the prevention of recurrent cerebrovascular events in patients with cryptogenic stroke and presumed paradoxical embolus. There is limited outcome data in patients treated with this therapy particularly for the newer devices. METHODS: Data from medical records, catheter, and echocardiography databases on 70 PFO procedures performed was collected prospectively. RESULTS: The cohort consisted of 70 patients (mean age 43.6 years, range 19 to 77 years), of whom 51% were male. The indications for closure were cryptogenic cerebrovascular accident (CVA) or transient ischemic attack (TIA) in 64 (91%) and peripheral emboli in two (2.8%) patients and cryptogenic ST-elevation myocardial infarction in one (1.4%), refractory migraine in one (1.4%), decompression sickness in one (1.4%), and orthodeoxia in one (1.4%) patient, respectively. All patients had demonstrated right-to-left shunting on bubble study. The procedures were guided by intracardiac echocardiography in 53%, transesophageal echocardiography in 39%, and the remainder by transthoracic echo alone. Devices used were the Amplatzer PFO Occluder (AGA Medical) (sizes 18-35 mm) in 49 (70%) and the Premere device (St. Jude Medical) in 21 (30%). In-hospital complications consisted of one significant groin hematoma with skin infection. Echocardiographic follow-up at 6 months revealed that most patients had no or trivial residual shunt (98.6%), while one patient (1.4%) had a mild residual shunt. At a median of 11 months' follow-up (range 1 month to 4.3 years), no patients (0%) experienced further CVA/TIAs or paradoxical embolic events during follow-up. CONCLUSION: PFO causing presumed paradoxical embolism can be closed percutaneously with a low rate of significant residual shunting and very few complications. Recurrent index events are uncommon at medium-term (up to 4 years) follow-up.

The role of natriuretic peptides in patients with chronic complex (mixed or multiple) heart valve disease.

N-terminal prohormone B-type natriuretic peptide (NT-proBNP) is an important biomarker of prognosis in heart failure and single valve disease. There are limited studies of complex valve disease. Patients with complex valve disease adopt a sedentary lifestyle, so symptoms may be difficult to detect. The authors aimed to determine whether NT-proBNP correlates with the severity of the valve lesion and underlying cardiac function and whether resting NT-proBNP predicts impaired peak VO(2) in patients with complex valve disease. Forty-five patients with complex moderate to severe stenosis or regurgitation of the heart valves underwent a clinical assessment, echocardiography, resting NT-proBNP assessment, and formal cardiopulmonary exercise testing. In a multivariate analysis, the log NT-proBNP (beta=-9.3, SE=1.9, P<.0001) and lean body weight (beta=0.59, SE=0.22, P=.01) were dominant independent predictors of peak VO(2). An NT-proBNP value of 84 pmol/L had 77% sensitivity and 70% specificity to predict impaired functional capacity, peak VO(2) <60% (predicted), area under the curve=0.80. Resting NT-proBNP was the best predictor of peak VO(2) in patients with complex valve disease, while symptoms and ejection fraction are a less reliable guide.

Complimentary roles for N-terminal pro-B-type natriuretic peptide and spirometry to assess functional capacity in patients with complex mixed heart valve disease.

BACKGROUND: Assessing the effects of valvular heart disease on functional capacity is important for optimal timing of surgery. AIM: To determine whether N-terminal pro-B type natriuretic peptide (NT-proBNP) and lung spirometry predict maximum oxygen consumption (pVO(2)) on cardio-pulmonary exercise testing in patients with mixed heart valve disease. METHODS: Forty-five clinically stable patients with moderate-severe stenosis and/or regurgitation of the aortic, mitral and/or tricuspid valves were studied. The ability of echocardiography, NT-proBNP, forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) to predict impaired pVO(2) was determined. RESULTS: On univariate analysis the natural logarithm of NT-proBNP explained more of the variation in pVO(2) (r(2) = 0.40, p < 0.0001) than valve severity score (r(2) = 0.20, p = 0.002), pulmonary artery pressure (r(2) = 0.21, p = 0.005), left atrial area index (r(2) = 0.25, p = 0.001) or LV ejection fraction (r(2) = 0.02, p = 0.4). Low lean body weight (r(2) = 0.21, p = 0.002), FEV1 (r(2) = 0.26, p = 0.0003) and FVC (r(2) = 0.20, p = 0.002) were also associated with pVO(2). In multi-variable analysis independent determinants of pVO(2) were NT-proBNP (r(2) = 0.27, p = 0.001), FVC (r(2) = 0.20, p = 0.0002) and lean body weight (r(2) = 0.23, p = 0.001). NT-proBNP and FVC together were better predictors of pVO(2) < 60% (C statistic = 0.83, 95% CI 0.71, 0.95) than either NT-proBNP (C = 0.80, 95% CI 0.66, 0.94) or FVC (C =0.73, 95% CI 0.57, 0.89) alone. NT-proBNP, FVC and age also predicted excessive ventilation on cardio-pulmonary exercise (combined r(2) = 0.54, p < 0.0001). CONCLUSION: In patients with mixed heart valve disease NT-proBNP and spirometry provide a more reliable assessment of functional capacity than assessment by echocardiography and symptoms alone.

Complex valve disease: pre-surgical functional capacity evaluation using peak oxygen consumption.

BACKGROUND AND AIM OF THE STUDY: Complex heart valve disease constitutes both mixed and multiple valve pathologies that coexist in a single heart. The chronicity of complex valve disease results in a slow decline in functional capacity. Currently, very few data exist relating to chronic complex valve disease. The clinical assessment of exertional dyspnea (NYHA class) is central to the decision to operate and predict a prognosis. Dyspnea causes significant functional limitations. Peak oxygen consumption (peak VO2) is the 'gold standard' of objectively measuring functional aerobic capacity, and is an important predictor of prognosis. The onset of dyspnea is the most common indication for valve surgery. The study aim, in patients with complex valve disease, was to: (i) objectively assess functional aerobic capacity using peak VO2; and (ii) compare the differences between NYHA classes I and II in relation to body composition, echocardiographic severity, and functional capacity METHODS: A total of 45 patients with complex valve disease, who had been referred for the timing of surgery, was evaluated. The control group comprised 15 healthy subjects. All patients underwent a clinical assessment (to determine NYHA class), echocardiography and cardiopulmonary testing (peak VO2). RESULTS: Patients with complex valve disease achieved significantly lower peak VO2 values than controls (16 +/- 5.9 versus 31.4 +/- 5.9 ml/kg/min; p = 0.0001). The peak VO2 (percentage predicted) was significantly different between asymptomatic (NYHA class I) patients (70.9 +/- 20%) and symptomatic (NYHA class II) patients (55.1 +/- 21%; p = 0.003), with an overlap between classes. There was no significant difference in the echocardiographic severity of the valve lesions between NYHA classes. In a multivariable regression analysis, the peak VO2 and VEN/VCO2 slope were powerful predictors of poor outcome (Hazards ratio 2.15, 5.62; p <0.05). CONCLUSION: Patients with complex valve disease show significant functional capacity impairment, which may be difficult to detect from their clinical presentation. Consequently, peak VO2 measurements are required for the objective evaluation of functional capacity. The detection of a decline in peak VO2 will improve the timing of valve replacement and repair, and avoid adverse outcomes.

Valsartan in the treatment of heart failure or left ventricular dysfunction after myocardial infarction.

The physiological role of the renin angiotensin aldosterone system (RAAS) is to maintain the integrity of the cardiovascular system. The effect of angiotensin II is mediated via the angiotensin type I receptor (AT1 ) resulting in vasoconstriction, sodium retention and myocyte growth changes. This causes myocardial remodeling which eventually leads to left ventricular hypertrophy, dilation and dysfunction. Inhibition of the RAAS with angiotensin converting enzyme (ACE) inhibitors after acute myocardial infarction has been shown to reduce cardiovascular morbidity and mortality. Angiotensin receptor blockers (ARBs) specifically inhibit the AT1 receptor. It has not been known until the performance of the VALIANT (valsartan in acute myocardial infarction trial) whether blockade of the angiotensin receptor with an ARB or combination of an ACE inhibitor and ARB leads to similar outcomes as an ACE inhibitor. The VALIANT trial demonstrated equal efficacy and non-inferiority of the ARB valsartan 160 mg bid compared with captopril 50 mg tds, when administered to high risk patients with left ventricular dysfunction or heart failure in the immediate post myocardial infarction period. The combination therapy showed no incremental benefit over ACE inhibition or an ARB alone and resulted in increased adverse effects. This review examines the role of valsartan in left ventricular dysfunction post myocardial infarction. We also discuss pharmacokinetics, dosing, side effects, and usage in the elderly.