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101.
Ultrasound myocardial cavitation-enabled treatment was applied to the SS-16BN rat model of hypertrophic cardiomyopathy for proof of the principle underlying myocardial reduction therapy. A focused ultrasound transducer was targeted using 10-MHz imaging (10 S, GE Vivid 7) to the left ventricular wall of anesthetized rats in a warmed water bath. Pulse bursts of 4-MPa peak rarefactional pressure amplitude were intermittently triggered 1:8 heartbeats during a 10-min infusion of a microbubble suspension. Methylprednisolone was given to reduce initial inflammation, and Losartan was given to reduce fibrosis in the healing tissue. At 28 d post therapy, myocardial cavitation-enabled treatment significantly reduced the targeted wall thickness by 16.2% (p?<0.01) relative to shams, with myocardial strain rate and endocardial displacement reduced by 34% and 29%, respectively, which are sufficient for therapeutic treatment. Premature electrocardiogram complexes and plasma troponin measurements were found to identify optimal and suboptimal treatment cohorts and would aid in achieving the desired impact. With clinical translation, myocardial cavitation-enabled treatment should fill the need for a new non-invasive hypertrophic cardiomyopathy therapy option.  相似文献   
102.
Apical hypertrophic cardiomyopathy (HCM) is an uncommon variant of HCM characterized by apical hypertrophy without the septal predominance seen in the majority of HCM cases. In 2% of patients, a concomitant left ventricular apical aneurysm is observed, which increases the risk of sudden death and adverse HCM‐related events. Multimodality imaging is helpful for appropriate identification of this particular morphologic pattern. Herein, we present a case of apical HCM with a left ventricular apical aneurysm, exemplifying the utility of a multimodality approach from resting electrocardiogram, transthoracic echocardiogram, left ventriculography, and cardiac magnetic resonance imaging, for proper risk stratification and treatment planning.  相似文献   
103.
ObjectivesThis study sought to evaluate the prognostic value of cardiac magnetic resonance (CMR)-derived mitral annular plane systolic excursion (MAPSE) in a large multicenter population of patients with hypertension.BackgroundIn patients with hypertension, cardiac abnormalities are powerful predictors of adverse outcomes. Long-axis mitral annular movement plays a fundamental role in cardiac mechanics and is an early marker for a number of pathological processes. Given the adverse consequences of cardiac involvement in hypertension, the authors hypothesized that lateral MAPSE may provide incremental prognostic information in these patients.MethodsConsecutive patients with hypertension and a clinical indication for CMR at 4 U.S. medical centers were included in this study (n = 1,735). Lateral MAPSE was measured in the 4-chamber cine view. The primary endpoint was all-cause death. Cox proportional hazards regression modeling was used to examine the association between lateral MAPSE and death. The incremental prognostic value of lateral MAPSE was assessed in nested models.ResultsOver a median follow-up period of 5.1 years, 235 patients died. By Kaplan-Meier analysis, risk of death was significantly higher in patients with a lateral MAPSE < median (10 mm) (log-rank; p < 0.0001). Lateral MAPSE was associated with risk of death after adjustment for clinical and imaging risk factors (hazard ratio [HR]: 1.402-per-millimeter decrease; p < 0.001). Addition of lateral MAPSE in this model resulted in significant improvement in the C-statistic (0.735 to 0.815; p < 0.0001). Continuous net reclassification improvement was 0.739 (95% confidence interval: 0.601 to 0.902). Lateral MAPSE remained significantly associated with death even after adjustment for feature tracking global longitudinal strain (HR: 1.192-per-millimeter decrease; p < 0.001). Lateral MAPSE was independently associated with death among the subgroups of patients with preserved ejection fraction (HR = 1.339; p < 0.001) and in those without history of myocardial infarction (HR: 1.390; p < 0.001).ConclusionsCMR-derived lateral MAPSE is a powerful, independent predictor of mortality in patients with hypertension and a clinical indication for CMR, incremental to common clinical and CMR risk factors. These findings may suggest a role for CMR-derived lateral MAPSE in identifying hypertensive patients at highest risk of death.  相似文献   
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IntroductionIn obstructive hypertrophic cardiomyopathy (HCM), alcohol septal ablation (ASA) can lead to gradient reduction and symptom improvement. We aimed to assess the efficacy and safety of ASA in a long-term outcome study.MethodsWe analyzed patients who underwent ASA over a seven-year period in a tertiary center. The primary echocardiographic endpoint was >50% reduction in left ventricular outflow tract (LVOT) gradient within a year of the procedure. The primary clinical endpoints were improvement in functional capacity and a combined endpoint of cardiac death and rehospitalization for cardiac cause. The follow-up period was 4.17±2.13 years.ResultsA total of 80 patients, mean age 63.9±12.3 years, 30.0% male, were analyzed. Baseline LVOT gradient was 96.3±34.6 mmHg and interventricular septal thickness was 21.6±3.1 mm. Minor complications were observed in 6.3% and major complications in 2.5%, and 8.8% received a permanent pacemaker.The primary echocardiographic endpoint was achieved by 85.7%. At three-month follow-up, LVOT gradient was 25.8±26.0 mmHg in the successful procedure group, compared to 69.2±35.6 mmHg in the other patients (p=0.001). At six months, LVOT gradient was 27.1±27.4 vs. 58.2±16.6 mmHg (p=0.024). Among 74 patients in NYHA class III/IV before the procedure, 57 (77%) improved to NHYA class I/II. The combined primary clinical endpoint (cardiac death and rehospitalization for cardiac cause) was observed in 27.5% (n=22). In the unsuccessful group, the combined endpoint was observed in 54.5%, compared to only 22.7% in the successful group. Only two patients died of cardiac causes.ConclusionASA is a safe procedure with a high success rate. Patients who achieved significant reductions in LVOT gradient suffered less cardiac death and rehospitalization for cardiac cause.  相似文献   
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ObjectiveOur objective was to investigate whether dobutamine stress echocardiography (DSE) could induce abnormal cardiac function in takotsubo stress cardiomyopathy (TSC) patients in a stable condition after the acute attack.Methods and ResultsThis was a case-control study and a substudy of the Stockholm Myocardial Infarction With Normal Coronaries (SMINC) study. Twenty-two patients with a previous episode of TSC and 22 sex- and age-matched control subjects were recruited from the SMINC study and investigated with the use of DSE. All TSC patients had a previous normal cardiovascular magnetic resonance investigation. Tissue Doppler imaging–derived time phases of the cardiac cycle were recorded to calculate myocardial performance index (MPI) to assess ventricular function. Compared with control subjects at rest, TSC patients had a slightly but significantly higher left ventricular MPI (LV-MPI; 0.53 vs 0.59; P = .01) and as a trend higher right ventricular MPI (0.38 vs 0.47; P = .08), although during DSE these variables did not differ significantly.ConclusionWe found no difference in standard diastolic parameters between TSC and control subjects, but a significant higher value in LV-MPI in the TSC group at rest. However, no such difference could be demonstrated during DSE between the groups, indicating that vulnerability to sympathetic stimulation does not persist in TSC patients.  相似文献   
109.
Cardiac transplantation is severely restricted by donor availability. Left ventricular dysfunction due to neurogenic stress cardiomyopathy is often seen during donor evaluation and often presents a clinical dilemma for procurement. We report a case of a 23-year-old man with severe left ventricular dysfunction whose heart was successfully procured for transplantation. The brief case report is followed by an extensive review of neurogenic stress cardiomyopathy as well as donor evaluation for cardiac transplantation in the setting of such cardiomyopathy.  相似文献   
110.
Cardiac involvement in systemic light chain amyloidosis (AL) is generally associated with a worse outcome, especially if other organs are also involved. We sought to determine whether concurrent cardiac and renal involvement were associated with a worse outcome than either organ alone. We identified 129 patients with AL, who received high‐dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto‐HCT) at our institution between 1997 and 2014. Ninety‐nine patients had either renal (group 1: n = 62, 62%), cardiac (group 2: n = 20, 20%), or both cardiac and renal (group 3: n = 17, 17%) involvement. The overall hematological response rate (CR+VGPR+PR) post‐auto‐HCT in groups 1, 2, and 3 was 69%, 74% and 82%, respectively (P = 0.62). Overall, organ response in groups 1, 2, and 3 was 39%, 42%, and 70%, respectively. The median PFS from auto‐HCT in groups 1, 2, and 3 was not reached (NR), 13.3 and 21 months, respectively (P = 0.02). The median OS in groups 1, 2, and 3 was 120, 46, and 60 months, respectively (P = 0.1). In conclusion, median PFS and OS in patients with concurrent cardiac and renal AL were comparable to patients with cardiac AL only, but worse than patients with renal AL.  相似文献   
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