Oh, Jae K.

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.

Abstract Aims We sought to evaluate associations between baseline sphericity index (SI) and clinical outcome, and changes in SI after coronary artery bypass graft (CABG) surgery with or without surgical ventricular reconstruction (SVR) in ischaemic cardiomyopathy patients enrolled in the SVR study (Hypothesis 2) of the Surgical Treatment for Ischemic Heart Failure (STICH) trial. Methods and results Among 1000 patients in the STICH SVR study, we evaluated 546 patients (255 randomized to CABG alone and 291 to CABG + SVR) whose baseline SI values were available. SI was not significantly different between treatment groups at baseline. After 4 months, SI had increased in the CABG + SVR group, but was unchanged in the CABG alone group (0.69 ± 0.10 to 0.77 ± 0.12 vs. 0.67 ± 0.07 to 0.66 ± 0.09, respectively; P < 0.001). SI did not significantly change from 4 months to 2 years in either group. Although LV end-systolic volume and EF improved significantly more in the CABG + SVR group compared with CABG alone, the severity of mitral regurgitation significantly improved only in the CABG alone group, and the estimated LV filling pressure (E/A ratio) increased only in the CABG + SVR group. Higher baseline SI was associated with worse survival after surgery (hazard ratio 1.21, 95% confidence interval 1.02 − 1.43; P = 0.026). Survival was not significantly different by treatment strategy. Conclusion Although SVR was designed to improve LV geometry, SI worsened after SVR despite improved LVEF and smaller LV volume. Survival was significantly better in patients with lower SI regardless of treatment strategy.

Background— The appropriate indication for coronary computed tomographic angiography (CTA) as a part of preoperative evaluation has not been defined yet. We investigated the value of coronary CTA in patients undergoing noncardiac surgery. Methods and Results— We included 844 patients (median age, 67 years; male sex, 62%) who underwent coronary CTA for screening of coronary artery disease before noncardiac surgery. Clinically determined revised cardiac risk index were compared with the extent and severity of coronary artery disease assessed by coronary CTA. Perioperative major cardiac event (PMCE), defined as cardiac death, myocardial infarction, or pulmonary edema within postoperative 30 days, developed in 25 patients (3.0%). Significant coronary CTA finding was defined as >3 any lesions with ≥1 (diameter stenosis ≥70%) stenosis based on the relationship between the severity of coronary artery disease and PMCE risk. The risk of PMCE was 14.0% in patients with significant CTA findings, whereas 2.2% of patients without significant CTA findings regardless of revised cardiac risk index score. The predictive performance of revised cardiac risk index could be improved significantly after addition of significant coronary CTA findings (c-statistics=0.631 versus 0.757; net reclassification improvement=0.923; integrated discrimination improvement=0.051). On the basis of revised cardiac risk index and coronary CTA, the risk of PMCE could be estimated with sensitivity, specificity, positive predictive value, and negative predictive value of 76%, 73%, 8%, and 99%, respectively. Conclusions— Addition of coronary CTA to clinical risk improved perioperative risk stratification. Absence of significant coronary CTA findings conferred low PMCE risk with high specificity and negative predictive value regardless of clinical risk. Coronary CTA may improve perioperative risk stratification in patients undergoing noncardiac surgery.

Background Myocardial strain imaging is a sensitive echocardiographic technique for identifying ventricular dysfunction. The aim of this study was to describe a reference range for right ventricular ( RV ) strain in subjects without cardiopulmonary disease and to report these values from a systematic review and meta‐analysis of the current literature. Methods Prospective online measurement of RV free wall longitudinal systolic strain using speckle tracking echocardiography ( STE ) was performed in 116 subjects with normal echocardiograms and without cardiopulmonary disease or risk factors. A systematic search of studies in EMBASE and Medline reporting RV strain values was performed through February 2014. Results The mean age was 48 ± 16 years and 58% were female. Mean RV strain was −26 ± 4%. Ten studies involving a total of 486 patients met our inclusion criteria. The mean age range was 43–57 years and 59% were female. All prior studies were performed with offline strain analysis, and 9 used a GE Healthcare strain analysis software system. The weighted estimate of RV free wall strain measured using tissue Doppler imaging (4 studies) was −27 ± 1% (95% confidence interval [ CI ] −30% to −25%) and with STE (8 studies, including the current study data) −27 ± 2% (95% CI −29% to −24%), respectively. Conclusions A reference range for RV strain in subjects without cardiopulmonary disease is presented. These data may help facilitate the routine clinical measurement of RV strain in patients referred for right heart echocardiography assessment.

Background— Coronary collateral flow is an alternative source of myocardial perfusion in patients with totally occluded coronary arteries. Clinical evaluation of collateral flow has been limited by the need of invasive measurements. We investigated whether noninvasive coronary computed tomographic angiography can evaluate the angiographic extent of coronary collateral flow. Methods and Results— We enrolled 325 coronary computed tomographic angiography cases with angiographically confirmed chronic total occlusion (median age, 63 years; men 83%). Transluminal attenuation gradient (TAG), which reflects the kinetics of contrast media in coronary artery, of an entire artery as well as of a distal vessel was assessed to evaluate the flow in entire vessel and distal vessel. TAGs were validated against visually assessed angiographic collateral connection and Rentrop grading. TAG of an entire artery increased consistently according to the angiographic extent of collateral flow ( P <0.001). Well-developed collaterals, defined by highest collateral connection and Rentrop grades (n=103), could be predicted by TAG of an entire artery (cutoff, ≥−7.6 Hounsfield units/10 mm; c -statistics, 0.72; sensitivity, 65%; specificity, 73%; positive predictive value, 52%; negative predictive value, 82%). TAG of a distal vessel could discriminate the antegrade (n=143) and retrograde (n=182) flows in distal artery (cutoff, 0.0 Hounsfield unit/10 mm; c -statistics, 0.88; sensitivity, 78%; specificity, 85%; positive predictive value, 87%; negative predictive value, 75%). Conclusions— TAG, an intracoronary attenuation-based analysis of coronary computed tomographic angiography, moderately reflected the functional extent and direction of collateral flow.