Natural history of MYH7-related dilated cardiomyopathy

Background

Variants in MYH7 are responsible for disease in 1–5% of patients with dilated cardiomyopathy (DCM); however, the clinical characteristics and natural history of MYH7-related DCM are poorly described.

Objectives

We sought to determine the phenotype and prognosis of MYH7-related DCM. We also evaluated the influence of variant location on phenotypic expression.

Methods

We studied clinical data from 147 individuals with DCM-causing MYH7 variants (47.6% females, 35.6±19.2 years) recruited from 29 international centers.

Results

At initial evaluation, 106 patients (72.1%) had DCM (LVEF 34.5±11.7%). Median follow-up was 4.5 years (interquartile range: 1.7–8.0). 23.7% carriers who were initially phenotype-negative developed DCM. Disease penetrance by 40 and 60 years was 46% and 88%, respectively, with 18 patients (16%) first diagnosed at <18 years. Thirty-six percent of patients with DCM met imaging criteria for LV non-compaction. During follow-up, 28% showed left ventricular reverse remodeling (LVRR). Overall incidence of end-stage heart failure (heart transplantation or heart failure related death) was 11.6% at 5 years. Overall major ventricular arrhythmia rate was low (1.0% at 5 years) even among patients with LVEF ≤35% (2.1% at 5 years). LV non-compaction was more prevalent in patients with variants in head domain (S1) (44.2%) compared with other domains (P<0.001). No differences among domain groups were found regarding LVRR, major ventricular arrhythmias or end-stage heart failure.

Conclusions

MYH7-related DCM is characterized by early age of onset, high penetrance, low rate of LVRR, and frequent progression to ESHF. Heart failure complications predominate over ventricular arrhythmias, even among patients with severe systolic disfunction.

Funding Acknowledgement

Type of funding sources: None.

Contemporary comparison of infective endocarditis caused by Candida albicans and Candida parapsilosis: a cohort study

Background

Although Candida albicans is the most frequent microorganism causing fungal endocarditis, its incidence has decreased during the last two decades, and that of non-albicans Candida species has risen. Among the last, Candida parapsilosis is of particular interest, representing the second most frequent Candida species causing IE1, 2.

Purpose

To compare the clinical course, imaging findings and outcomes among patients with IE caused by C. albicans (CAIE) and C. parapsilosis (CPIE) in order to identify organism-specific peculiarities.

Methods

From January 1998 to June 2020, all consecutive cases of CAIE and CPIE (n=16), admitted to a hospital network composed of 3 tertiary hospitals and prospectively recruited on a multipurpose database, were retrospectively analysed. All cases were evaluated by the Endocarditis Team (ET) and underwent a thorough diagnostic work-up, including blood cultures at admission, transoesophageal echocardiography (TEE) and culture of the valves extracted at surgery. Other imaging tests, such as PET/CT, were performed at the ET's discretion. Diagnosis of IE was made according to the modified Duke criteria until 20153, and the European Society of Cardiology (ESC) 2015 modified diagnostic criteria thereafter4.

Results

Eight patients were diagnosed with CAIE and 8 with CPIE. Regarding predisposing conditions, a higher prevalence of prosthetic valves was found among CPIE. Other population's baseline information is shown in Table 1. Compared to CAIE, CPIE presented a longer time from the beginning of symptoms to hospital admission (40 vs 7 days; p=0.062), but no differences regarding signs and symptoms were observed. Aortic location was the most frequent infection side in both groups, but prosthetic valve involvement was remarkably more frequent among patients with CPIE (75% vs 37.5%; p=0.315. Figure 1). CPIE also presented a higher rate of positive blood cultures at admission (100% vs 62.5%; p=0.200), persistently blood cultures 48–72 hours after antifungals initiation (100% vs 0%; p=0.021) and positive valve cultures (83.3% vs 57.1%; p=0.569). No differences regarding TEE and other imaging tests findings were observed. All patients but 4 underwent valve replacement surgery. No differences in in-hospital complications or in mortality were observed between CAIE and CPIE, even after adjusting for therapeutic management.

Conclusions

Compared to CAIE, CPIE presented a more frequent involvement of prosthetic valves, a longer course of symptoms before admission and a bigger proportion of persistently positive blood cultures. In-hospital complications and mortality were similar between the two groups.

Funding Acknowledgement

Type of funding sources: None. Table 1. Population characteristicsFigure 1. Valve involvement distribution