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Concept: Left ventricle

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INTRODUCTION: Blunt cardiac rupture is an exceedingly rare injury. CASE PRESENTATION: We report a case of blunt cardiac trauma in a 43-year-old Caucasian German mother with pectus excavatum who presented after a car accident in which she had been sitting in the front seat holding her two-year-old boy in her arms. The mother was awake and alert during the initial two hours after the accident but then proceeded to hemodynamically collapse. The child did not sustain any severe injuries. Intraoperatively, a combined one-cm laceration of the left atrium and right ventricle was found. CONCLUSION: Patients with pectus excavatum have an increased risk for cardiac rupture after blunt chest trauma because of compression between the sternum and spine. Therefore, patients with pectus excavatum and blunt chest trauma should be admitted to a Level I Trauma Center with a high degree of suspicion.

Concepts: Heart, Pectus excavatum, Chest, Sternum, Ventricle, Left ventricle, Physical trauma, Chest trauma

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The introduction of the so-called newer-generation transcatheter aortic valve implantation (TAVI) devices has led to a dramatic reduction in the incidence of complications associated with the procedure. However, preliminary data suggest that conduction abnormalities (particularly new-onset atrioventricular block and left bundle branch block) remain a frequent complication post TAVI. Although inconsistencies across studies are apparent, new-onset conduction abnormalities post TAVI may be associated with higher incidences of mortality, sudden cardiac death and left ventricular dysfunction. Strategies intended both to reduce the risk and to improve the management of such complications are clearly warranted. In fact, the indication and timing of permanent pacemaker implantation are frequently individualised according to centre and/or operator preference. Currently, studies assessing the impact of these complications and the optimal indications for permanent cardiac pacing are underway. In this article, we review the data available on the incidence and impact of conduction disturbances following TAVI, and propose a strategy for the management of such complications.

Concepts: Cardiology, Heart, Cardiac arrest, Cardiac electrophysiology, Left ventricle, Cardiac pacemaker, Sinoatrial node, Transcutaneous pacing

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Patients with chronic heart failure (HF) secondary to left ventricular systolic dysfunction (LVSD) are frequently deficient in vitamin D. Low vitamin D levels are associated with a worse prognosis.

Concepts: Vitamin D, Blood, Cardiology, Heart, Ventricle, Mitral valve, Left ventricle, Beriberi

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Background Cardiac pacemakers are limited by device-related complications, notably infection and problems related to pacemaker leads. We studied a miniaturized, fully self-contained leadless pacemaker that is nonsurgically implanted in the right ventricle with the use of a catheter. Methods In this multicenter study, we implanted an active-fixation leadless cardiac pacemaker in patients who required permanent single-chamber ventricular pacing. The primary efficacy end point was both an acceptable pacing threshold (≤2.0 V at 0.4 msec) and an acceptable sensing amplitude (R wave ≥5.0 mV, or a value equal to or greater than the value at implantation) through 6 months. The primary safety end point was freedom from device-related serious adverse events through 6 months. In this ongoing study, the prespecified analysis of the primary end points was performed on data from the first 300 patients who completed 6 months of follow-up (primary cohort). The rates of the efficacy end point and safety end point were compared with performance goals (based on historical data) of 85% and 86%, respectively. Additional outcomes were assessed in all 526 patients who were enrolled as of June 2015 (the total cohort). Results The leadless pacemaker was successfully implanted in 504 of the 526 patients in the total cohort (95.8%). The intention-to-treat primary efficacy end point was met in 270 of the 300 patients in the primary cohort (90.0%; 95% confidence interval [CI], 86.0 to 93.2, P=0.007), and the primary safety end point was met in 280 of the 300 patients (93.3%; 95% CI, 89.9 to 95.9; P<0.001). At 6 months, device-related serious adverse events were observed in 6.7% of the patients; events included device dislodgement with percutaneous retrieval (in 1.7%), cardiac perforation (in 1.3%), and pacing-threshold elevation requiring percutaneous retrieval and device replacement (in 1.3%). Conclusions The leadless cardiac pacemaker met prespecified pacing and sensing requirements in the large majority of patients. Device-related serious adverse events occurred in approximately 1 in 15 patients. (Funded by St. Jude Medical; LEADLESS II ClinicalTrials.gov number, NCT02030418 .).

Concepts: Clinical trial, Heart, Right ventricle, Ventricle, Left ventricle, Cardiac pacemaker, Artificial pacemaker, Transcutaneous pacing

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The diagnosis of heart failure may be challenging because symptoms are rather nonspecific. Elevated left ventricular (LV) filling pressure may be used to confirm the diagnosis, but cardiac catheterization is often not practical. Echocardiographic indexes are therefore used as markers of filling pressure.

Concepts: Blood, Cardiology, Heart, Right ventricle, Ventricle, Aorta, Mitral valve, Left ventricle

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Background Ischemic mitral regurgitation is associated with a substantial risk of death. Practice guidelines recommend surgery for patients with a severe form of this condition but acknowledge that the supporting evidence for repair or replacement is limited. Methods We randomly assigned 251 patients with severe ischemic mitral regurgitation to undergo either mitral-valve repair or chordal-sparing replacement in order to evaluate efficacy and safety. The primary end point was the left ventricular end-systolic volume index (LVESVI) at 12 months, as assessed with the use of a Wilcoxon rank-sum test in which deaths were categorized below the lowest LVESVI rank. Results At 12 months, the mean LVESVI among surviving patients was 54.6±25.0 ml per square meter of body-surface area in the repair group and 60.7±31.5 ml per square meter in the replacement group (mean change from baseline, -6.6 and -6.8 ml per square meter, respectively). The rate of death was 14.3% in the repair group and 17.6% in the replacement group (hazard ratio with repair, 0.79; 95% confidence interval, 0.42 to 1.47; P=0.45 by the log-rank test). There was no significant between-group difference in LVESVI after adjustment for death (z score, 1.33; P=0.18). The rate of moderate or severe recurrence of mitral regurgitation at 12 months was higher in the repair group than in the replacement group (32.6% vs. 2.3%, P<0.001). There were no significant between-group differences in the rate of a composite of major adverse cardiac or cerebrovascular events, in functional status, or in quality of life at 12 months. Conclusions We observed no significant difference in left ventricular reverse remodeling or survival at 12 months between patients who underwent mitral-valve repair and those who underwent mitral-valve replacement. Replacement provided a more durable correction of mitral regurgitation, but there was no significant between-group difference in clinical outcomes. (Funded by the National Institutes of Health and the Canadian Institutes of Health; ClinicalTrials.gov number, NCT00807040 .).

Concepts: Statistics, Death, Heart, Statistical significance, Standard deviation, Mitral valve, Left ventricle, Mitral regurgitation

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Background In a randomized trial comparing mitral-valve repair with mitral-valve replacement in patients with severe ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI), survival, or adverse events at 1 year after surgery. However, patients in the repair group had significantly more recurrences of moderate or severe mitral regurgitation. We now report the 2-year outcomes of this trial. Methods We randomly assigned 251 patients to mitral-valve repair or replacement. Patients were followed for 2 years, and clinical and echocardiographic outcomes were assessed. Results Among surviving patients, the mean (±SD) 2-year LVESVI was 52.6±27.7 ml per square meter of body-surface area with mitral-valve repair and 60.6±39.0 ml per square meter with mitral-valve replacement (mean changes from baseline, -9.0 ml per square meter and -6.5 ml per square meter, respectively). Two-year mortality was 19.0% in the repair group and 23.2% in the replacement group (hazard ratio in the repair group, 0.79; 95% confidence interval, 0.46 to 1.35; P=0.39). The rank-based assessment of LVESVI at 2 years (incorporating deaths) showed no significant between-group difference (z score=-1.32, P=0.19). The rate of recurrence of moderate or severe mitral regurgitation over 2 years was higher in the repair group than in the replacement group (58.8% vs. 3.8%, P<0.001). There were no significant between-group differences in rates of serious adverse events and overall readmissions, but patients in the repair group had more serious adverse events related to heart failure (P=0.05) and cardiovascular readmissions (P=0.01). On the Minnesota Living with Heart Failure questionnaire, there was a trend toward greater improvement in the replacement group (P=0.07). Conclusions In patients undergoing mitral-valve repair or replacement for severe ischemic mitral regurgitation, we observed no significant between-group difference in left ventricular reverse remodeling or survival at 2 years. Mitral regurgitation recurred more frequently in the repair group, resulting in more heart-failure-related adverse events and cardiovascular admissions. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00807040 .).

Concepts: Clinical trial, Blood, Cardiology, Heart, Mitral valve, Left ventricle, Mitral regurgitation, Recurrence relation

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Purpose: The Ironman (IM) triathlon is a popular ultra endurance competition, consisting of a 3.8km swimming, 180.2km cycling, and a 42.2km run. The aim of this study was to investigate predictors of IM race time, comparing echocardiographic findings, anthropometric measures, and training characteristics.Methods: Amateur IM athletes (ATHL) participating in the Zurich IM race in 2010 were included. Participants were examined the day before the race by a comprehensive echocardiographic examination. Moreover, anthropometric measurements were obtained the same day. During the 3 months before the race, each IM-ATHL maintained a detailed training diary. Recorded data were related to total Ironman race time.Results: Thirty-eight Ironman finishers (average age 38±9 years, 32 male [84%]) were evaluated. Average total race time was 684±89 minutes. For right ventricular fractional area change (average: 45±7%, Spearman-ρ=-0.33; p=0.05) a weak correlation with race time was observed. Race performance exhibited stronger associations with percent body fat (15.2±5.6%, ρ=0.56; p=0.001), speed in running training (11.7±1.2 km/h, ρ=-0.52; p=0.002), and left ventricular myocardial mass index (98±24 g/m, ρ=-0.42; p=0.009). The strongest association was found between race time and right ventricular end-diastolic area (22±4 cm, ρ=-0.64; p<0.0001). In multivariate analysis, right ventricular end-diastolic area (beta=-16.7, 95% confidence interval: -27.3-[-6.1]; p=0.003) and percent body fat (beta=6.8, 95% confidence interval: 1.1-12.6; p=0.02) were independently predictive of Ironman race time.Conclusions: In amateur IM-ATHL, RV end-diastole area and percent body fat were independently related to race performance. RV end-diastolic area was the strongest predictor of race time. The role of the RV in endurance exercise may thus be more important than previously thought and needs to be further studied.

Concepts: Heart, Interval finite element, Anthropometry, Right ventricle, Ventricle, Left ventricle, Bulbus cordis, Primitive ventricle

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Reoperation for failing stentless aortic valve replacement is a technically demanding procedure that has traditionally been tackled in one of two ways: either root replacement or the more conservative option of implanting a stented valve within the valve. We sought to determine the relative operative risks, follow-up status and medium to long-term survival of these two methods.

Concepts: Derivative, Left ventricle, Aortic valve, Valve, Valve Corporation, Aortic valve replacement, Aortic insufficiency

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: We determined whether left ventricular hypertrophy (LVH) which exceeds that predicted from workload [inappropriate LV mass (LVMinappr)] is associated with reduced left ventricle (LV) systolic chamber function independent of and more closely than absolute or indexed left ventricular mass (LVM).

Concepts: Cardiology, Left ventricular hypertrophy, Right ventricle, Ventricle, Ventricular hypertrophy, Left ventricle