Citations

Background— Low-gradient severe aortic stenosis with preserved ejection fraction is an increasingly recognized entity, and symptomatic patients may benefit from aortic valve replacement. However, systemic hypertension frequently coexists with low-gradient severe aortic stenosis, which itself may cause elevated left ventricular (LV) filling pressures with resultant symptoms of dyspnea. Methods and Results— Symptomatic patients with hypertension (aortic systolic pressure >140 mm Hg) and low-gradient (mean gradient <40 mm Hg) severe aortic stenosis (aortic valve area <1 cm 2 ) with preserved ejection fraction (ejection fraction >50%) who underwent invasive hemodynamic catheterization of the left and right sides of the heart received infusion of intravenous sodium nitroprusside to reduce blood pressure and arterial afterload. At baseline, patients had severe hypertension (aortic systolic pressure, 176±26 mm Hg), pulmonary hypertension (mean pressure, 39±12 mm Hg), elevated LV end-diastolic pressure (19±5 mm Hg), and reduced stroke volume (33±8 mL/m 2 ). All measures of afterload were reduced with nitroprusside ( P <0.001 for all). Nitroprusside reduced mean pulmonary artery pressure (25±10 mm Hg) and LV end-diastolic pressure (11±5 mm Hg; P <0.001 for both compared with baseline). Aortic valve area (0.86±0.11 to 1.02±0.16 cm 2 ; P =0.001) and mean gradient (27±5 to 29±6 mm Hg; P =0.02) increased with nitroprusside. Conclusions— Systemic hypertension in low-gradient severe aortic stenosis with preserved ejection fraction is associated with elevated LV filling pressures and pulmonary hypertension. Treatment of hypertension with vasodilator therapy results in a lowering of the total LV afterload, with a decrease in LV filling pressures and pulmonary artery pressures. These findings have important implications for the management of patients with low-gradient severe aortic stenosis with preserved ejection fraction and hypertension.

Retroperitoneal fibrosis is a rare condition characterized by the presence of inflammatory and fibrous retroperitoneal tissue that surrounds and often encases abdominal structures. In this report we describe an unusual presentation of retroperitoneal fibrosis and inferior vena cava (IVC) obstruction that was unidentified by noninvasive testing and ultimately diagnosed using exercise right heart catheterization and venography. Exercise hemodynamic catheterization revealed a high pressure gradient across the IVC obstruction during exercise that resulted in reduced preload and inappropriately low cardiac output reserve. The patient ultimately underwent angioplasty and stenting of the obstruction resulting in resolution of his symptoms. © 2013 Wiley Periodicals, Inc.

Background— The pathophysiology of low flow, low gradient severe aortic stenosis (LGSAS) with preserved ejection fraction is poorly understood. It has been proposed that abnormalities of arterial circulation are a major contributor to this syndrome. Methods and Results— We invasively examined systemic arterial afterload (effective arterial elastance, Ea; total arterial compliance, Ca; and systemic vascular resistance index) in patients with LGSAS (mean gradient, <40 mm Hg; aortic valve area, <1.0 cm 2 ) and preserved ejection fraction (≥50%), and compared these findings with patients with high gradient (≥40 mm Hg) severe aortic stenosis (HGSAS) and moderate AS (mean gradient, <40 mm Hg; aortic valve area, >1.0 cm 2 ). Patients with LGSAS (n=36), HGSAS (n=31), and moderate AS (n=19) were similar with respect to age, sex, body size, symptoms, comorbidities, and ejection fraction. Aortic valve area was similar between groups with LGSAS and HGSAS, but the patients with LGSAS had reduced stroke volume index and cardiac index ( P =0.003 for both). In comparison with patients with HGSAS and moderate AS, measures of afterload, including Ea (4.02±0.98 versus 3.13±0.81 and 3.06±0.79 mm Hg·m 2 /mL; P <0.0001) and systemic vascular resistance index (3116±799 versus 2515±645 and 2380±546 dyn·s·m 2 /cm 5 ; P =0.001), were significantly higher in LGSAS, whereas Ca was lower (0.46±0.16 versus 0.57±0.13 and 0.59±0.19 mL/m 2 per mm Hg; P =0.002). All invasive measures of arterial afterload were related to stroke volume index. Conclusions— Patients with LGSAS and preserved ejection fraction display elevated arterial afterload compared with patients with HGSAS and moderate AS. These findings identify systemic arterial effects that contribute to the hemodynamic presentation in patients with LGSAS and help to further define this entity.

Background— The clinical efficacy of alcohol septal ablation for obstructive hypertrophic cardiomyopathy (HCM) has been demonstrated, but the long-term effects of the procedure remain uncertain. This study examined the survival of patients after septal ablation performed in a tertiary HCM referral center. Methods and Results— We examined 177 patients (mean age, 64 years; 68% women) who underwent septal ablation at our institution. Over a follow-up of 5.7 years, survival free of all mortality was no different than the expected survival for a comparable general population, and similar to that of age- and sex-matched patients who underwent isolated surgical myectomy (8-year survival estimate, 79% versus 79%; P =0.64). For the end point of documented sudden cardiac death or unknown cause of death, the incidence per 100 person-year follow-up was 1.31 (95% confidence interval, 0.60–2.38). Residual left ventricular outflow tract gradient after ablation was an independent predictor of long-term survival free of any death. Conclusions— In this nonrandomized study of carefully selected patients undergoing septal ablation by experienced operators in a tertiary referral HCM center, long-term survival was favorable and similar to that of an age- and sex-matched general population, and to patients undergoing surgical myectomy, as well, without an increased risk of sudden cardiac death.

Atrial and brain natriuretic peptides (ANP and BNP) are produced by the heart, and their plasma concentrations are increased in human chronic congestive heart failure. Although separate studies have suggested that circulating levels of the biologically active C-terminal ANP, the biologically inactive N-terminal ANP, and BNP may have diagnostic utility in the detection of left ventricular systolic dysfunction or left ventricular hypertrophy, no studies have directly assessed the relative value of these peptides prospectively. We therefore designed this study to compare the relative ability of the different natriuretic peptides to detect abnormal left ventricular systolic and diastolic function and left ventricular hypertrophy. Using a prospective study design, we investigated 94 patients referred for cardiac catheterization and 15 age-matched normal subjects. The diagnostic abilities of elevated plasma C-terminal ANP, N-terminal ANP-(1-30), and BNP concentrations to identify systolic dysfunction (ejection fraction <45%), diastolic dysfunction (time constant of left ventricular relaxation >55 milliseconds, left ventricular end-diastolic pressure >18 mm Hg), and left ventricular hypertrophy (left ventricular mass index >120 g/m 2 ) were objectively compared by receiver operating characteristic analysis. The areas under the receiver operating characteristic curve of BNP for detecting each of these abnormalities ranged from 0.715 to 0.908 and were significantly greater than those of C-terminal ANP or N-terminal ANP-(1-30). The sensitivity and specificity of an elevated plasma BNP, which we defined as greater than the mean+3 SD of the 15 age-matched normal subjects, were 0.83 and 0.77, respectively, for detecting ejection fraction less than 45%, 0.85 and 0.70 for detecting the time constant of left ventricular relaxation greater than 55 milliseconds, 0.63 and 0.76 for detecting left ventricular end-diastolic pressure greater than 18 mm Hg, and 0.81 and 0.85 for detecting left ventricular mass index greater than 120 g/m 2 . The use of BNP and one other peptide increased sensitivity (0.90 to 0.96), albeit with lower specificity (0.56 to 0.71). An elevated plasma BNP was a more powerful marker of left ventricular systolic dysfunction, left ventricular diastolic dysfunction, and left ventricular hypertrophy than C-terminal ANP or N-terminal ANP-(1-30) in this population of patients with suspected cardiac disease. Measurement of BNP alone or in combination with C-terminal ANP or N-terminal ANP-(1-30) has potential utility for the detection of altered left ventricular structure and function in a patient population at risk for cardiovascular disease.

BackgroundQuantitative Doppler echocardiography and proximal flow convergence methods are validated techniques for quantifying mitral regurgitation. However, the clinical interpretation of the values calculated is hindered by the absence of calibration of ranges of severity in large numbers of patients.Methods and ResultsIn 180 consecutive patients (men, 62%; mean age±SD, 66±11 years), the results of Doppler quantification of isolated mitral regurgitation were calibrated by use of left ventricular angiographic grading performed within 3 months in routine practice and without intervening events. The thresholds of the quantitative variables corresponding to the angiographic grades were identified by maximizing the sum of sensitivity and specificity and minimizing their difference. The mitral regurgitation grade by angiography was 2.7±1.3. The mean value and correlation with angiographic grades for effective regurgitant orifice were 43±37 mm andr=.79 (P<.0001); for regurgitant volume, 62±45 mL andr=.80 (P<.0001); and for regurgitant fraction, 45±17% andr=.78 (P<.0001). Despite some overlap, differences between mitral regurgitation grades were all significant (allP<.05). The thresholds for severe mitral regurgitation (grade 4) were 60 mL, 50%, and 40 mm2for regurgitant volume, regurgitant fraction, and orifice, respectively.ConclusionsIn routine practice in large numbers of patients in a clinical laboratory, Doppler echocardiographic quantification of mitral regurgitation shows highly significant correlation with qualitative angiographic grades. Despite an expected overlap between classes, the calibration by angiography of grading ranges for the quantitative variables provides a framework for their interpretation and allows the definition in clinical practice of thresholds for severe mitral regurgitation.