Elevation of high-sensitivity cardiac troponin T and left ventricular remodelling in hypertrophic cardiomyopathy.

AIMS: Hypertrophic cardiomyopathy (HCM) is generally associated with mild disability and normal life expectancy. On the other hand, once the end-stage phase of HCM characterized by left ventricular (LV) ejection fraction < 50% is established, patients with this subtype have a poor prognosis. This study clarifies the clinical parameters associated with progression to end-stage HCM. METHODS AND RESULTS: We retrospectively studied 157 HCM patients (age 59.9 ± 14.2 years, 104 men) with preserved LV systolic function in whom subsequent echocardiographic data were obtained for a period of >1 year. HCM progressed to end-stage HCM in 13 patients (8.3%) of the 157 patients during a mean follow-up period of 6.3 ± 2.8 years. Compared with patients who did not reach end-stage HCM at the last evaluation, patients with progression to the end-stage phase had lower ejection fraction, larger LV size, more enlarged left atrial diameter, longer follow-up period, and higher frequency of an elevated concentration of high-sensitivity cardiac troponin T (hs-cTnT; >0.014 ng/mL) at registration. Multivariate analysis revealed that elevated hs-cTnT was a significant predictor independent of lower LV ejection fraction for progression to end-stage HCM. Furthermore, in patients with elevated hs-cTnT levels, LV ejection fraction became significantly lower, LV end-diastolic diameter increased, and LV wall thickness decreased during the follow-up period, whereas those parameters did not change in the normal hs-cTnT group. CONCLUSIONS: In patients with HCM, an elevated hs-cTnT was associated with progression of LV remodelling, and this biomarker can be useful for predicting progression to the end-stage phase.

Lifelong Clinical Impact of the Presence of Sarcomere Gene Mutation in Japanese Patients With Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is mainly caused by mutations in sarcomere genes. Regarding the clinical implications of genetic information, little is known about the lifelong clinical effect of sarcomere mutations in Japanese HCM patients.Methods and Results:We studied 211 consecutive Japanese patients with HCM who had agreed to genetic testing between 2003 and 2013. Genetic analyses were performed by direct DNA sequencing in the 6 common sarcomere genes (MYH7,MYBPC3,TNNT2,TNNI3,TPM1,ACTC). Through variant filtering, 21 mutations were identified in 67 patients. After excluding 8 patients whose variants were determined as having uncertain significance, finally 203 patients (130 men, age at study entry: 61.8±14.1 years) were investigated for clinical presentation and course. At the time of study entry, patients with mutations were younger, had more frequent non-sustained ventricular tachycardia, had greater interventricular wall thickness, were more frequently in the dilated phase and less frequently had apical HCM. Through their lifetimes, a total of 98 HCM-related morbid events occurred in 72 patients. Survival analysis revealed that patients with sarcomere gene mutations experienced those morbid events significantly more frequently, and this tendency was more prominent for lethal arrhythmic events. CONCLUSIONS: In our HCM cohort, patients with sarcomere gene mutations had poorer lifelong outcome. Genetic information is considered important for better management of HCM.

Preoperative Clinical Features and High Pulmonary Wedge Pressure with a Discordant Pattern as Prognostic Factor in Hemodialysis Patients with Severe Aortic Valve Stenosis.

Hemodialysis (HD) is one of the important risks for the development of cardiovascular disease, including aortic valve stenosis (AS). Although aortic valve replacement (AVR) is a beneficial treatment for AS, HD patients are known to show a high rate of mortality after AVR than non-HD patients.We retrospectively studied 109 patients who underwent AVR for severe AS, 18 of which were HD patients. Survival rate after AVR, preoperative clinical data, and surgical procedure were investigated.In preoperative clinical features, left ventricular end-diastolic diameter was larger, intraventricular septum thickness (IVST) was thicker, left ventricular mass index (LVMI) was higher, left ventricular ejection fraction was lower, E/e' was higher, and pulmonary arterial wedge pressure (PAWP) was higher in the HD group than in the non-HD group. During a follow-up period of 3.2 ± 2.3 years after AVR, patients receiving HD had a worse prognosis than those without HD treatment: the 3-year survival rate after surgery in the HD group was 36.2% and that in the non-HD group was 84.9%. With regard to prognostic factors in the whole cohort, significant differences were found in IVST, LVMI, E/e', PAWP, and HD. In patients receiving HD, abnormally high PAWP for their right atrial pressure (RAP) was observed, suggesting that PAWP and RAP were discordant, and univariate analysis revealed that high PAWP was the only predictor of mortality in HD patients after surgery.Preoperative PAWP with a discordant pattern in HD patients might be an important prognostic predictor after AVR.

A case report of an uncommon presentation of 99mtechnetium pyrophosphate scintigraphy in transthyretin cardiac amyloidosis: A potential diagnostic pitfall, pseudo-positive or pseudo-negative?

99mTechnetium pyrophosphate (99mTc-PYP) scintigraphy has shown utility for diagnosis of transthyretin (ATTR) cardiac amyloidosis with a high sensitivity and specificity. However, in clinical practice, a protocol and a method of analysis of this modality are not yet unified. We present a case of ATTR cardiac amyloidosis showing a positive cardiac uptake in planar imaging but no myocardial uptake in single-photon emission computed tomography/computed tomography (SPECT/CT) fusion imaging on 99mTc-PYP scintigraphy. We considered this tracer accumulation in the cardiac blood pool to be an inconclusive study. In this report, we focus on an inconclusive study case as a potential pitfall of 99mTc-PYP scintigraphy and discuss the interpretation of 99mTc-PYP scintigraphy findings with using both planar and SPECT/CT imaging for improvement of diagnostic accuracy for ATTR cardiac amyloidosis. .

Prediction of Medium-Term Mortality in Japanese Patients With Wild-Type Transthyretin Amyloidosis.

Background: The prognostic factors in Japanese patients with wild-type transthyretin amyloidosis (ATTRwt) have not been elucidated. Methods and Results: In this study we retrospectively analyzed the clinical characteristics and outcomes of 47 patients with ATTRwt (mean (±SD) age at diagnosis 80.3±4.6 years; 41 males). Fifteen patients died within 2 years of their diagnosis. Receiver operating characteristic and Kaplan-Meier analyses revealed that the best predictors of 2-year mortality were low serum albumin (≤3.75 g/dL), elevated high-sensitivity cardiac troponin T (hs-cTnT; >0.086 ng/mL), and reduced left ventricular ejection fraction (LVEF; <50%). According to the total number of these 3 risk factors, patients were stratified into 4 subgroups: low risk (no risk factors; n=15), intermediate-low risk (1 risk factor; n=15), intermediate-high risk (2 risk factors; n=7), and high risk (3 risk factors; n=10). The estimated 2-year survival rate of patients classified as low risk, intermediate-low risk, intermediate-high risk, and high risk was 93%, 80%, 83%, and 11%, respectively (P<0.001). Conclusions: Low serum albumin, elevated hs-cTnT, and reduced LVEF are associated with a worse prognosis in Japanese patients with ATTRwt. The combination of these factors may be useful for predicting medium-term mortality in patients with ATTRwt.

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.

Beneficial Effect of Pimobendan for Severe Heart Failure Due to Transthyretin Cardiac Amyloidosis.

Objective Transthyretin amyloidosis, particularly wild-type transthyretin amyloid cardiomyopathy (ATTRwt), has been recognized as an important cause of morbidity and mortality in the aging population. However, it is difficult to manage heart failure itself in patients with cardiac amyloidosis. Methods We herein report the management of heart failure in an elderly patient with severe heart failure due to ATTRwt. We also review the clinical situation in an additional seven patients with cardiac amyloidosis who were administered pimobendan in our hospital. Results We treated a 71-year-old man with refractory heart failure due to ATTRwt. He was expected to be dependent on dobutamine infusion. We administered pimobendan and successfully improved his symptoms and hemodynamic status to allow his discharge from the hospital. An additional retrospective investigation observed that there were eight patients with ATTR amyloidosis who were administered pimobendan. Although all of the patients at the time of administration of pimobendan were NYHA class III or IV with repeated hospitalization for heart failure, pimobendan seemed to be effective for improving symptoms and enabling patients to be discharged and receive outpatient medical care. Furthermore, focusing on the changes in some biomarkers, we found that the brain natriuretic peptide and estimated glomerular filtration rate values improved after the administration of pimobendan in 5 consecutive patients for whom data were available without additional treatment (p=0.018 and 0.051, respectively). Conclusion In clinical practice, pimobendan seems to have beneficial effects in heart failure management for improving physical activities and the quality of life in patients with transthyretin cardiac amyloidosis.

Clinical Profile of Thromboembolic Events in Patients With Hypertrophic Cardiomyopathy in a Regional Japanese Cohort　- Results From Kochi RYOMA Study.

BACKGROUND: There is limited information about the clinical profiles of patients with hypertrophic cardiomyopathy (HCM) and thromboembolic events in a community-based Japanese patient cohort.Methods and Results:In 2004, we established a cardiomyopathy registration network in Kochi Prefecture that comprised 9 hospitals, and finally 293 patients with HCM were followed. The mean age at registration was 63±14 years, and 197 patients (67%) were men. At registration, 86 patients (29%) had documented atrial fibrillation (AF). During a mean follow-up period of 6.1±3.2 years, thromboembolic events, including 3 embolic stroke deaths, occurred in 23 patients. The 5-year embolic event rate was 5.5%. During the follow-up period, an additional 31 patients (11%) had documentation of AF and finally a total of 117 patients (40%) developed AF. The 5-year embolic event rate in those 117 patients with AF was 12.3%. Of the 23 patients with embolic events, 12 had AF prior to the embolic complications and another 6 had documented AF after thromboembolism. AF was not detected in the remaining 5 patients. The CHADS2score did not correlate with the embolic outcome in HCM patients. CONCLUSIONS: In this community-based registry, thromboembolic events were not rare in patients with HCM. All patients with HCM in whom AF develops should be given anticoagulation therapy regardless of their CHADS2score.

Patients' Characteristics and Clinical Course of Hypertrophic Cardiomyopathy in a Regional Japanese Cohort　- Results From Kochi RYOMA Study.

BACKGROUND: There have been few studies on the clinical course of hypertrophic cardiomyopathy (HCM) in a community-based patient cohort in Japan.Methods and Results:In 2004, we established a cardiomyopathy registration network in Kochi Prefecture (the Kochi RYOMA study) that consisted 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, and 197 patients (67%) were male. HCM-related deaths occurred in 23 patients during a mean follow-up period of 6.1±3.2 years. The HCM-related 5-year survival rate was 94%. In addition, a total of 77 cardiovascular events that were clinically severe occurred in 70 patients, and the HCM-related 5-year event-free rate was 80%. Multivariate Cox proportional hazards model analysis showed that the presence of NYHA class III at registration was a significant predictor of HCM-related deaths and that the presence of atrial fibrillation, lower fractional shortening and presence of left ventricular outflow tract obstruction in addition to NYHA class III were significant predictors of cardiovascular events. CONCLUSIONS: In our unselected registry in an aged Japanese community, HCM mortality was favorable, but one-fifth of the patients commonly suffered from HCM-related adverse cardiovascular events during the 5-year follow-up period. Careful management of HCM patients is needed, particularly for those with the above-mentioned clinical determinants.