Dilated Phase Of Hypertrophic Cardiomyopathy Research Articles

Metabolic remodeling and calcium handling abnormality in induced pluripotent stem cell-derived cardiomyocytes in dilated phase of hypertrophic cardiomyopathy with MYBPC3 frameshift mutation

Hypertrophic cardiomyopathy (HCM) is an inherited disorder characterized by left ventricular hypertrophy and diastolic dysfunction, and increases the risk of arrhythmias and heart failure. Some patients with HCM develop a dilated phase of hypertrophic cardiomyopathy (D-HCM) and have poor prognosis; however, its pathogenesis is unclear and few pathological models exist. This study established disease-specific human induced pluripotent stem cells (iPSCs) from a patient with D-HCM harboring a mutation in MYBPC3 (c.1377delC), a common causative gene of HCM, and investigated the associated pathophysiological mechanisms using disease-specific iPSC-derived cardiomyocytes (iPSC-CMs). We confirmed the expression of pluripotent markers and the ability to differentiate into three germ layers in D-HCM patient-derived iPSCs (D-HCM iPSCs). D-HCM iPSC-CMs exhibited disrupted myocardial sarcomere structures and an increased number of damaged mitochondria. Ca2+ imaging showed increased abnormal Ca2+ signaling and prolonged decay time in D-HCM iPSC-CMs. Cell metabolic analysis revealed increased basal respiration, maximal respiration, and spare-respiratory capacity in D-HCM iPSC-CMs. RNA sequencing also showed an increased expression of mitochondrial electron transport system-related genes. D-HCM iPSC-CMs showed abnormal Ca2+ handling and hypermetabolic state, similar to that previously reported for HCM patient-derived iPSC-CMs. Although further studies are required, this is expected to be a useful pathological model for D-HCM.

In vivo mitral valve repair for the transplanted donor heart in orthotopic heart transplantation

A 53-year-old woman with the dilated phase of hypertrophic cardiomyopathy underwent orthotopic heart transplantation. The donor heart was evaluated as normal preoperatively without mitral regurgitation or the left atrium dilation, transplanted using the modified bicaval technique. Although the heart beat satisfactorily after aortic declamping, massive mitral regurgitation was observed without any prolapse or annular dilation. Because of the difficulty in weaning from cardiopulmonary bypass, a second aortic cross-clamp was applied, and we detached the inferior vena cava and the right side of the left atrial anastomosis to approach the mitral valve, obtaining a satisfactory exposure. No abnormalities were observed in the mitral valve leaflets, annulus or subvalvular apparatus. Subsequent in vivo mitral annuloplasty using prosthetic full ring successfully controlled the regurgitation, and the patient was easily weaned from cardiopulmonary bypass. She discharged to home with good mitral valve and cardiac functions. And the patient has been doing well without any recurrence of MR or heart failure for over a year after surgery.

The Myocardial Accumulation of Aggregated Desmin Protein in a Case of Desminopathy with a de novo DES p.R406W Mutation.

Desminopathy is a cardiac and skeletal myopathy caused by disease-causing variants in the desmin (DES) gene and represents a subgroup of myofibrillar myopathies, where cytoplasmic desmin-postive immunoreactivity is the pathological hallmark. We herein report a 28-year-old Japanese man who was initially diagnosed with sporadic hypertrophic cardiomyopathy with atrioventricular block at 9 years old and developed weakness in the soft palate and extremities. The myocardial tissue dissected during implantation of the ventricular-assisted device showed a dilated phase of hypertrophic cardiomyopathy and intracellular accumulation of proteinase K-resistant desmin aggregates. Genetic testing confirmed a de novo mutation of DES, which has already been linked to desminopathy. As the molecular diagnosis of desminopathy is challenging, particularly if patients show predominantly cardiac signs and a routine skeletal muscle biopsy is unavailable, these characteristic pathological findings of endomyocardial proteinase K-resistant desmin aggregates might aid in clinical practice.

Identification of patients with dilated phase of hypertrophic cardiomyopathy using a convolutional neural network applied to multiple, dual, and single lead electrocardiograms.

This study sought to develop an artificial intelligence-derived model to detect the dilated phase of hypertrophic cardiomyopathy (dHCM) on digital electrocardiography (ECG) and to evaluate the performance of the model applied to multiple-lead or single-lead ECG. This is a retrospective analysis using a single-center prospective cohort study (Shinken Database 2010-2017, n=19,170). After excluding those without a normal P wave on index ECG (n=1,831) and adding dHCM patients registered before 2009 (n=39), 17,378 digital ECGs were used. Totally 54 dHCM patients were identified of which 11 diagnosed at baseline, 4 developed during the time course, and 39 registered before 2009. The performance of the convolutional neural network (CNN) model for detecting dHCM was evaluated using eight-lead (I, II, and V1-6), single-lead, and double-lead (I, II) ECGs with the five-fold cross validation method. The area under the curve (AUC) of the CNN model to detect dHCM (n=54) with eight-lead ECG was 0.929 (standard deviation [SD]: 0.025) and the odds ratio was 38.64 (SD 9.10). Among the single-lead and double-lead ECGs, the AUC was highest with the single lead of V5 (0.953 [SD: 0.038]), with an odds ratio of 58.89 (SD:68.56). Compared with the performance of eight-lead ECG, the most similar performance was achieved with the model with a single V5 lead, suggesting that this single-lead ECG can be an alternative to eight-lead ECG for the screening of dHCM.

Abstract 12354: Novel Coronavirus Disease 2019 Infection in a Cohort of Patients With Phenotypic Hypertrophic Cardiomyopathy: An Extended Report

Background: Patients with preexisting heart disease suffer more severe outcomes after COVID-19. Hypertrophic cardiomyopathy (HCM) is a common inherited cardiac conditions. We previously reported incidence and outcomes of COVID-19 in HCM in early days of the pandemic. We report results from an expanded and extended HCM cohort. Methods: 343 patients with HCM [age 59±17 years, 55% men, 19% NYHA class >1, 63% obstructive, 14% septal reduction therapy, 24% positive family history, 42% selectively genotyped (43% positive for pathogenic mutations), 22% implantable cardioverter-defibrillator (ICD) implants, 27% paroxysmal or permanent atrial fibrillation (AF), 4% AF ablation] were evaluated for COVID-19 from December 2019 to May 2022. Results. Overall, 54 (16%) patients were diagnosed with COVID-19 [56% men, age 55±17 years, 60% obstructive HCM, 5.5% dilated phase HCM, 28% positive family history, 15% genotype positive, 28% with ICD, 17% NYHA class >1, 31% AF]. There were 289 patients without COVID-19 [55% men, age 58±17 years, 63% obstructive HCM, 3% dilated phase HCM, 23% positive family history, 17% genotype positive, 21% with ICD, 19% NYHA class >1, 27% AF]. Patients with COVID-19 were slightly younger (55±17 vs 58±17 years, p 0.046) and more often had dilated phase HCM (5.5% vs 3%) and more often had ICD (28% vs 21%). Eleven (20%) patients with COVID-19 were hospitalized and 1 (2%) died of the disease. Compared to those with mild disease, hospitalized patients with COVID-19 were more often men (82% vs 49%, p 0.04), older (age 59±15 vs. 54±18 years), with obstructive phenotype (73% vs 56%) and with NYHA class >1 symptoms (27% vs 12%). In the studied patient cohort 70% had at least one dose of COVID-19 vaccine. Prior to the infection 63% of patients had no vaccination against SARS-CoV2. Among hospitalized patients 9 (82%) had no vaccination and 2 (18%) were vaccinated and had mild disease. Conclusions. Although Covid-19 infection rate (16%) in studied cohort was slightly lower than in general US population (~25%), hospitalization rate was higher (20% vs 9%) with similar death rates (1-2%). Older man with symptomatic obstructive HCM phenotype noted to have higher risk for hospitalization. Patients with vaccination against SARS-Cov2 tended to require less hospitalization.

Catheter ablation of ventricular tachycardia in dilated-phase hypertrophic cardiomyopathy: Substrate characterization and ablation outcome.

Catheter ablation is a therapeutic option to suppress ventricular tachycardia (VT) in the setting of dilated-phase hypertrophic cardiomyopathy (DHCM). However, the characteristics of the arrhythmogenic substrate and the ablation outcome are not fully illustrated. A total of 23 ablation procedures for drug-refractory sustained monomorphic VTs in 13 DHCM patients (60 ± 11 years, one female, the left ventricular [LV] ejection fraction 39% ± 9%, the LV mass index 156 ± 39 g/m2 ) were performed. The distribution of VT substrate as endocardial or epicardial/intramural was based on detailed mapping and ablation response during VT. Two patients underwent ablation of sustained monomorphic VT that was not scar-mediated tachycardia. Of the remaining 11 patients, eight (73%) patients had VT substrate in the basal regions, most frequently at the epicardial and/or intramural basal antero-septum. None of the patients had VT substrate located at the LV inferolateral region. Ablation at the right ventricular septum and the aortic cusps was done in four and five patients, respectively. Other approaches including bipolar and chemical ablations, were done in three and two patients, respectively. Six (55%) out of 11 patients (two patients lost follow-up) had VT recurrence. All the six patients had basal substrate. However, anti-tachycardia pacing was sufficient for VT termination except in one patient. Catheter ablation of VT in patients with DHCM is challenging because of the predominant basal anteroseptal epicardial/intramural location of arrhythmogenic substrate. An ablation approach from multiple sites and/or adjunctive interventional techniques are often required.

A New Modification for Anastomosing HeartMate 3 Apical Cuff for a Small Left Ventricle

<h3>Introduction</h3> A preoperative small left ventricular size has been associated with higher mortality and complications after left ventricular assist device (LVAD) implantation. The small left ventricle (LV) may result in repeated suction events and inflow obstruction, possibly leading to pump thrombosis and malfunction and thromboembolism. The inflow cannula length of HeartMate 3 is 22 mm, and the CT-measured protrusion depth of inflow cannula into the LV was 13.5 ± 1.0 mm in our previous HeartMate 3 series (16 patients). Based on the concept that making the protrusion depth shallow should decrease the risk for suction event, we adopted a hand-made apical cuff, whose actual thickness was 6mm, modified by stacking three layers of felt on the original PTFE felt during HeartMate 3 implantation for a small LV patient. Here, we report two cases in which this modified apical cuff was used. <h3>Case Report</h3> One patient is a 47-year-old woman with idiopathic dilated cardiomyopathy who underwent implantation of a HeartMate 3. Preoperative echocardiography showed a small left ventricular end-diastolic dimension (LVDd) of 49 mm. We anastomosed the described-above modified apical cuff in a core then sew technique. Postoperative LVDd was 30 mm and cardiac index was 2.7 L/min/m² under optimized pump setting. Another is a 58-year-old woman with dilated phase of hypertrophic cardiomyopathy who underwent implantation of a HeartMate 3. The preoperative LVDd of this patient was 48 mm. The same modified apical cuff was secured in a core then sew technique after resection of the intraventricular muscle through the apical coring hole. Postoperative LVDd was 37 mm and cardiac index was 2.2 L/min/m² under optimized pump setting. Both patients experienced no significant suction event or adverse events and are still waiting for heart transplantation as an outpatient. <h3>Summary</h3> This modified apical cuff is promising for achieving adequate pump performance of HeartMate 3 and possibly improving the outcomes of LVAD therapy in patients with the small LV.

Pathogenic variant of RBM20 in a multiplex family with hypertrophic cardiomyopathy

RBM20 is a disease-causing gene associated with dilated cardiomyopathy (DCM). The proband presented with the dilated phase of hypertrophic cardiomyopathy (HCM), and the mother also suffered from HCM. A missense variant of RBM20, p.Arg636His, previously reported as pathogenic in several families with DCM, was found in both the proband and the mother. Therefore, RBM20 p.Arg636His could be the causative variant for this familial HCM, and RBM20 might be a novel causative gene for HCM.

Outcomes of hypertrophic cardiomyopathy in Japanese children: a retrospective cohort study.

There has been no multicenter study on the prognosis of pediatric hypertrophic cardiomyopathy (HCM) in Japan. Therefore, we conducted a retrospective multicenter observational study on the long-term survival rate in patients diagnosed with HCM under the age of 18 between 1990 and 2014. Twenty institutions participated. A total of 180 patients were identified. The median age at diagnosis was 5.8years old and median duration of observation was 8.3years. Although six patients (3%) deteriorated into the dilated phase of HCM, no patient received heart transplantation. Freedom from death at 1, 5, 10, and 20years were 97%, 92%, 84%, and 80%, respectively. There were 26 deaths. Among them, 11 patients died suddenly, presumably due to arrhythmia, and 15 patients died of heart failure. The presence of heart failure symptoms and a greater cardiothoracic ratio were significant risk factors for heart failure-related death. There were no significant risk factors identified for arrhythmia-related death. In conclusion, the prognosis of pediatric HCM in Japan is good and similar to those reported in population-based studies in the United States and Australia. Significant risk factors for heart failure-related death were identified in pediatric patients with HCM in Japan.

Predictive scoring method for declining left ventricular ejection fraction in hypertrophic cardiomyopathy

Abstract Background The transition to the dilated phase, as well as sudden cardiac death, is one of the most undesirable scenarios for patients with hypertrophic cardiomyopathy (HCM). Although the dilated phase of HCM (DHCM) is defined as left ventricular ejection fraction (LVEF) &amp;lt;50%, the significance of mildly reduced LVEF is also in the spotlight because this status is considered as a transitional phase of DHCM. Establishing predictive scoring method for declining LVEF is expected. Methods Of the 319 HCM patients enrolled in the J-HCM registry from our hospital, we analyzed 168 patients (101 male and 57 female, 63.4±14.8 years), after excluding those who underwent PTSMA, who received pacemaker implantation, and who died or dropped out within 2 years. The patients were divided into two groups according to the change of LVEF from the baseline. During the follow-up period (62.0±109.9 months), LVEF decreased by ≥10% in 37 patients (Group D) whereas it did not in 131 patients (Group C). We compared clinical parameters between the two groups to identify the factors affecting the declining LVEF by ≥10% and examined whether the scoring method using those parameters can predict it. Results At the baseline, the percentage of male and diabetic patients was greater in group D than group C (76% vs. 55%, P=0.023 and 38% vs. 12%, P&amp;lt;0.001, respectively). The patients with complete right bundle branch block, wide QRS complex (&amp;gt;100msec), and atrial fibrillation tended to be more in group D than group C (all P&amp;lt;0.1). When the scoring method with those 5 parameters was tested by giving 1 point each, the risk of the declining LVEF was tended to be higher in the patients with 2 or 3 point and significantly higher in those with 4 point compared with that in those with point 0 (OR 2.042, 95% CI 0.983–4.243, P=0.056 and OR 12.000, 95% CI 2.313–62.267, P=0.003, respectively). Conclusions This scoring method appeared to be useful to stratify the risk of the decrease in LVEF in patients with HCM. The validation study is warranted in a larger population. Funding Acknowledgement Type of funding sources: None.

Dilated phase of hypertrophic cardiomyopathy: high-risk reconstructive surgery as an alternative to heart transplantation

The authors report the diagnosis and surgical treatment of 5 patients with dilated phase of hypertrophic cardiomyopathy (HCM). Features of these patients are progressive heart failure, double-level blood flow obstruction and the risk of apical aneurysms. Reconstructive remodeling surgery is a reasonable alternative to heart transplantation despite the existing risk.

Sudden Cardiac Death-Relevant Events of Hypertrophic Cardiomyopathy in a Regional Japanese Cohort - Results From the Kochi RYOMA Study.

Background: Sudden cardiac death (SCD) is a most devastating complication of hypertrophic cardiomyopathy (HCM). The aim of this study was to clarify the clinical features of HCM in patients who experienced SCD-relevant events in an aged Japanese community.Methods and Results: In 2004, we established a cardiomyopathy registration network in Kochi Prefecture, and herein report on 293 patients with HCM who are followed as part of the registry. The mean (±SD) age at registration and diagnosis was 63±14 and 56±16 years, respectively. SCD-relevant events occurred in 19 patients during a mean follow-up period of 6.1±3.2 years (incidence rate 1.0%/year): sudden death in 9 patients, successful recovery from cardiopulmonary arrest in 4 patients, and appropriate implantable cardioverter–defibrillator discharge in 6 patients. At registration, 13 patients were in the dilated phase of HCM (D-HCM). During the follow-up period, HCM developed to D-HCM in 21 patients; thus, 34 patients in total had D-HCM. Multivariate analysis revealed that D-HCM at registration or during follow-up and detection of non-sustained ventricular tachycardia (NSVT) during follow-up were significant predictors of SCD-relevant events.Conclusions: In this HCM population in an aged Japanese community, the annual rate of SCD-relevant events was 1.0%. HCM developed to D-HCM in a considerable number of patients, and D-HCM and NSVT were shown to be independently associated with an increased risk of SCD-relevant events.

Evaluation of myocardial glucose metabolism in hypertrophic cardiomyopathy using 18F-fluorodeoxyglucose positron emission tomography.

BackgroundThe purposes of this study were to assess the usefulness of myocardial 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) for evaluating myocardial metabolic status in hypertrophic cardiomyopathy (HCM) and the therapeutic efficacy of alcohol septal ablation (ASA) in hypertrophic obstructive cardiomyopathy (HOCM).MethodsThirty HCM patients (64.4±10.5 years, 14 male, 12 hypertrophic non-obstructive cardiomyopathy [HNCM], 16 HOCM, and 2 dilated phase of HCM) underwent 18F-FDG-PET/CT. 18F-FDG uptake was semi-quantitatively evaluated using an uptake score in each 17 segment and the entire LV or regional standardized uptake value (SUV).Results18F-FDG uptake was observed mostly in a hypertrophied myocardium in HNCM patients, whereas 18F-FDG was extensively accumulated beyond the hypertrophied myocardium in HOCM patients. There was a positive correlation between the summed uptake score of 18F-FDG and high-sensitive troponin T level in HNCM patients (r = 0.603, p = 0.049), whereas the score was positively correlated with brain natriuretic peptide level (r = 0.614, p = 0.011) in HOCM patients. In 10 patients who received ASA, the maximum SUV of the entire LV was significantly reduced from 5.6±2.6 to 3.2±2.1 (p = 0.040) after ASA. Reduction of that maximum SUV was particularly significant in the lateral region (from 5.5±2.6 to 2.9 ±2.2, p = 0.024) but not significant in the anteroseptal region (from 4.5±2.6 to 2.9±1.6, p = 0.12).ConclusionExtensive 18F-FDG uptake beyond the hypertrophied myocardium was observed in HOCM. ASA attenuates 18F-FDG uptake in a remote lateral myocardium.

SP3-6 - A Multi-Center Observational Study of Dilated Phase of Hypertrophic Cardiomyopathy

Introduction: Clinical features of dilated phase of hypertrophic cardiomyopathy (dHCM) have not been fully elucidated. Purpose: The purpose of this study was to reveal clinical characteristics, treatment, and prognosis in Japanese patients with dHCM. Methods and Results: Forty six dHCM patients (59.2 ± 15.6 years old, male 61%) were registered at multiple centers in Japan from April 2015 to June 2017. The interval from the onset of symptoms to the first diagnosis of HCM was 5.8 ± 8.0 years, and from HCM to the transition to dHCM was 11.7 ± 7.9 years thereafter. At the time of detection of HCM, the transition to dHCM, and the registration, left ventricular (LV) diastolic diameter, was 45.3 ± 9.8, 54.4 ± 6.5, and 56.4 ± 8.0 mm, respectively. LV ejection fraction (EF) was 70.1 ± 13.9, 44.8 ± 8.1, and 36.3 ± 9.5%, and the thickness of intraventricular septum was 21.0 ± 7.3, 14.8 ± 4.4, and 12.3 ± 3.7 mm. At registration, New York Heart Association functional class III or IV was 35%. dHCM patients were treated with renin-angiotensin system inhibitors in 82%, b-blocker in 96%, loop diuretics in 62%, and amiodarone in 38%. Twenty nine patients (63%) had prior heart failure hospitalization (HF). Patients with prior HF hospitalization were more likely to have a history of atrial fibrillation and showed lower LVEF compared with those without it. Conclusions: HCM slowly develops into dHCM over about 10 years. dHCM patients have a high rate of heart failure hospitalization.

P5-1 - Different Types of Heart Failure in Hypertrophic Cardiomyopathy in a Community-Based Japanese Cohort: Results From Kochi RYOMA Study

Background: There have been very few studies on the clinical course of hypertrophic cardiomyopathy (HCM) in a community-based patient cohort in Japan. This time, we focused on types of heart failure (HF) in our unselected registry. Methods and Results: In 2004, we established a cardiomyopathy registration network in Kochi Prefecture, Japan, named Kochi RYOMA study, consisting of 9 hospitals, and finally 293 patients with HCM were followed. The ages at registration and at diagnosis were 63 ± 14 and 56 ± 16 years, respectively. HF events defined as HF deaths and hospitalization for HF, occurred in 35 patients during a mean follow-up period of 6.1 years. Of those patients, 14 patients were due to dilated phase of HCM (D-HCM) defined as left ventricular (LV) systolic dysfunction of ejection fraction <50%. In the remaining 21 patients, 7 patients were associated with LV outflow obstruction, 2 patients had severe mitral regurgitation due to organic abnormality of mitral valve. The other 12 patients were considered to be mainly related to LV diastolic dysfunction. Conclusions: In our unselected registry in an aged Japanese community, HF is an important complication of HCM and 40% of the patients with HF events were associated with D-HCM and 20% were due to LV outflow obstruction. Recognition of the multi-factors evoked to HF is important in HCM.

O34-5 - 64-year-old Man Suffering Dilated Phase of HCM Who Died of Intracerebral Hemorrhage Before Exchanging to Implantable LVAD from Extracorporeal

From 17 years old, hypertension was pointed out. At 52 years old the LV function decreased, therefore detailed examinations were performed at a university hospital. But he could not get etiological diagnosis. Antihypertensive treatment was started then. At 58 years old severe heart failure was developed, he was diagnosed as dilated phase of hypertrophic cardiomyopathy. At 63 years old he received the ICD implantation for non-sustained VT attacks, and participated in a cardiac rehabilitation program. At 64 years old he was admitted to another university hospital for severe heart failure and the left lower leg cellulitis. He was transferred to our hospital in order to undergo surgical treatment including extracorporeal LVAD implantation for severe heart failure, severe MR, severe TR, chronic atrial fibrillation, dependence on inotropic agents, renal dysfunction on CHDF, and bacteremia. MVR with bileaflet preservation, LAA closure, full MAZE procedure, TAP, and extracorporeal LVAD implantation were performed with the aim of bridge to decision. LVAD off test was performed on 21st POD. It revealed that removal of the LVAD was impossible. We applied for heart transplantation registration on 50th POD and got the approval immediately. However, before changing to implantable LVAD, he was struck with an intracerebral hemorrhage on 58th POD. He died on 95th POD. The autopsy findings will be presented at the meeting.

Unexpected bioprosthetic mitral valve thrombus during left ventricular assist device implantation

Acute bioprosthetic valve thrombosis can occur after surgery and sometimes cause hemodynamic instability and cardiogenic shock. Risk factors for bioprosthetic valve thrombosis are hypercoagulability, atrial fibrillation, atrial dilatation, low cardiac function, and lack of anticoagulation therapy. The authors present a case of severe mitral stenosis due to bioprosthetic valve thrombus. The patient was diagnosed with dilated-phase hypertrophic cardiomyopathy and underwent mitral valve replacement. He required venoarterial extracorporeal membrane oxygenation (VA-ECMO) due to extremely low cardiac output and was scheduled for left ventricular assist device (LVAD) implantation. Transesophageal echocardiographic examination before LVAD implantation revealed severe mitral stenosis due to bioprosthetic mitral valve thrombus, which was not detected by transthoracic echocardiography in the intensive care unit and contributed to the low cardiac function. The thrombus was removed through an unscheduled left atriotomy before LVAD implantation. The possibility of bioprosthetic valve thrombosis must be considered when the patient is dependent on VA-ECMO support. Early transesophageal echocardiographic examination of the bioprosthetic valve may be helpful and contribute to surgical decision-making.

Clinical outcome of cardiac resynchronization therapy in dilated-phase hypertrophic cardiomyopathy.

BackgroundsClinical trials have demonstrated that cardiac resynchronization therapy (CRT) is effective in patients with “non-ischemic cardiomyopathy”. However, patients with dilated-phase hypertrophic cardiomyopathy (DHCM) have been generally excluded from such trials. We aimed to compare the clinical outcome of CRT in patients with DHCM, idiopathic dilated cardiomyopathy (IDCM), or ischemic cardiomyopathy (ICM).MethodsA total of 312 consecutive patients (DHCM: n = 16; IDCM: n = 231; ICM: n = 65) undergoing CRT in Fuwai hospital were studied respectively. Response to CRT was defined as reduction in left ventricular end-systolic volume (LVESV) ≥ 15% at 6-month follow-up.ResultsCompared with DHCM, IDCM was associated with a lower total mortality (HR: 0.35, 95% CI: 0.13–0.90), cardiac mortality (HR: 0.29; 95% CI: 0.11–0.77), and total mortality or heart failure (HF) hospitalizations (HR: 0.34, 95% CI: 0.17–0.69), independent of known confounders. Compared with DHCM, the total mortality, cardiac mortality and total mortality or HF hospitalizations favored ICM but were not statistically significant (HR: 0.59, 95% CI: 0.22–1.61; HR: 0.59, 95% CI: 0.21–1.63; HR: 0.54, 95% CI: 0.26–1.15; respectively). Response rate to CRT was lower in the DHCM group than the other two groups although the differences didn't reach statistical significance.ConclusionsCompared with IDCM, DHCM was associated with a worse outcome after CRT. The clinical outcome of DHCM patients receiving CRT was similar to or even worse than that of ICM patients. These indicate that DHCM behaves very differently after CRT.

Prognostic Significance of Non-Dilated Left Ventricular Size and Mitral Regurgitation in Patients With Dilated Phase of Hypertrophic Cardiomyopathy.

Although a subtype of hypertrophic cardiomyopathy (HCM), dilated phase of HCM (D-HCM) characterized by left ventricular (LV) systolic dysfunction, has been reported to have a poor prognosis, some patients with D-HCM survive for a relatively long period. The degree of LV dilatation and functional mitral regurgitation (MR) are generally thought to be important predictors of poor prognosis in patients with LV systolic dysfunction. However, there is little information available on the relations among LV size, presence of significant MR, and prognosis in D-HCM patients.We retrospectively studied 31 patients with D-HCM to determine whether echocardiographic assessment of LV size and MR provides incremental prognostic information.During a follow-up period of 5.6 ± 4.2 years, there were 13 cardiovascular deaths. When the patients were divided into two groups by LV size at diagnosis of D-HCM, a non-dilated LV group (LV end-diastolic diameter (LVEDD) < 50 mm, n = 9) and a dilated LV group (LVEDD ≥ 50 mm, n = 22), the clinical course in the non-dilated LV group was significantly worse. As for the clinical impact of MR, no patient in the non-dilated LV group showed significant MR and 7 of the patients with dilated LV size showed significant MR during follow-up. Once significant MR was reached, cardiovascular deaths were significantly more frequent in patients with MR.Patients with D-HCM, particularly those with less LV dilatation at diagnosis of dilated phase and with significant MR during follow-up, have a poor prognosis.

The diagnostic role of cardiac magnetic resonance used "first and last time in life" in a patient with a suspected dilated phase of hypertrophic cardiomyopathy.

The diagnostic role of cardiac magnetic resonance used "first and last time in life" in a patient with a suspected dilated phase of hypertrophic cardiomyopathy.