Thromboembolism in Patients with Hypertrophic Cardiomyopathy

Managing Stroke Prevention in Hypertrophic Obstructive Cardiomyopathy (HOCM) Patients Without Confirmed Persistent Atrial Fibrillation: A Dilemma of Anticoagulation

Hypertrophic obstructive cardiomyopathy (HOCM) is a genetic cardiovascular disorder characterized by the thickening of the heart muscle, particularly the left ventricle. It is a leading cause of sudden cardiac death in young individuals. HOCM is associated with various complications, including arrhythmias and an increased risk of stroke. Patients with HOCM are at an increased risk of stroke due to the development of atrial fibrillation (AFib), a common arrhythmia observed in HOCM. AFib can result in the formation of blood clots in the atria, which may subsequently embolize the brain, causing a stroke. However, not all HOCM patients develop persistent AFib, leading to uncertainty regarding the appropriate management of stroke prevention in these cases. This case study aims to explore the management of recurrent cerebrovascular events (CVA) in a patient with HOCM who does not have confirmed persistent AFib. The argument revolves around whether anticoagulation should be offered for secondary stroke prevention in HOCM patients without a confirmed diagnosis of persistent AFib.

3-Year outcomes after left atrial appendage closure in patients with nonvalvular atrial fibrillation: cardiomyopathy related with increased death and stroke rate

INTRODUCTION

Left atrial appendage closure (LAAC) is a novel treatment for stroke prevention in high-risk patients with non-valvular atrial fibrillation (NVAF). However, the long-term outcomes after LAAC in Chinese NVAF patients are still lacking.

METHODS

This was a single-center, bidirectional, nonrandomized registered study. Patients who underwent LAAC implantation from May 2014 to April 2021 in a large Chinese center were enrolled. The primary endpoint was combined all-cause death and stroke.

RESULTS

From May 2014 to April 2021, a total of 673 NVAF patients were enrolled. The overall successful implantation rate was 97.62% (657 of 673). The rate of perioperative adverse events was 1.19% (8 of 673), including 3 cardiac tamponades, 2 ischemic strokes, one device-related thrombus (DRT) and 2 device dislocations. 604 (92.24%) patients completed the follow-up, the median follow-up period was 36.9 months (IQR 24.8-56.5 months). 16 stroke events occurred in 15 patients (one patient suffered from both hemorrhagic and ischemic strokes). 13 patients (2.15%) had ischemic stroke, and the fatal rate was 0.33% (2 of 604). 3 patients (0.15%) suffered from hemorrhagic stroke, and the fatal rate was 0.17% (1 of 604). The overall stroke rate was 0.74% per-year. The combined death and stroke rate was 1.93% per-year. In the multivariate Cox regression analysis, age ≥ 75 (hazard ratio 2.264, 95% CI 1.074-4.772, P = 0.032) and ventricular cardiomyopathy (hazard ratio 2.738, 95% CI 1.060-7.071, P = 0.037) were independent predictors of combined mortality and stroke.

CONCLUSION

The overall successful implantation rate of LAAC was 97.62% and the rate of perioperative adverse events was 1.19% in this study, and the stroke rate was 0.74% per year during the long-term follow-up. Age ≥ 75 years and ventricular cardiomyopathy were independent predictors of the primary endpoint. Trial registration This study was retrospectively registered.

Ischaemic events in hypertrophic cardiomyopathy patients with and without atrial fibrillation: a systematic review and meta-analysis

Hypertrophic cardiomyopathy predisposes to acute cerebrovascular events including ischaemic stroke, transient ischaemic attack and systemic thromboembolism. Atrial fibrillation confers even higher risk. We aim to report the incidence of these complications and to investigate the impact of atrial fibrillation on the ischaemic risk in patients with hypertrophic cardiomyopathy. A literature search was performed on PubMed, Scopus, Embase/Ovid and Cochrane library from inception to 20th March 2021. We compared the incidence of ischaemic strokes, transient ischaemic attack, non-specified thromboembolism events and systemic thromboembolism in hypertrophic cardiomyopathy patients with or without atrial fibrillation. Non-specified thromboembolism events in our paper referred to thromboembolic events whereby types were not specified in the studies. Meta-analysis was performed using StataSE 16 software, and heterogeneity was assessed using I² test. A total of 713 studies were identified. Thirty-five articles with 42,570 patients were included. The pooled incidence of stroke/ transient ischaemic attack was 7.45% (95% confidence interval [CI] 5.80-9.52, p < 0.001) across 24 studies with a total of 37,643 hypertrophic cardiomyopathy patients. Atrial fibrillation significantly increased the risk of total stroke/ transient ischaemic attack (Risk Ratio 3.26, 95% CI 1.75-6.08, p < 0.001, I² = 76.0). The incidence of stroke/ transient ischaemic attack was 9.30% (95% CI 6.64-12.87, p = 0.316) in the apical hypertrophic cardiomyopathy subgroup. Concomitant atrial fibrillation in hypertrophic cardiomyopathy increases the risk of thromboembolic events including ischaemic stroke and transient ischaemic attack. The apical subgroup shows a similar risk of acute cerebrovascular events as the overall hypertrophic cardiomyopathy population.

Risk factors, clinical features, and outcomes of patients with hypertrophic cardiomyopathy complicated by ischemic stroke: A single-center retrospective study

Objective

This study aimed to explore risk factors, clinical features, and prognosis of patients with hypertrophic cardiomyopathy (HCM) complicated by ischemic stroke (IS).

Methods

We conducted a retrospective analysis of all HCM patient data and a 1-year follow-up study.

Results

Totally, 506 patients with HCM, including 71 with IS, were enrolled. Older age (≥63 years) was associated with an increased risk of IS in HCM patients (OR = 1.045, 95% CI: 1.018-1.072, p = 0.001). Among 37 patients complicated by IS, 22 (59.5%, 22/37) manifested as cardioembolism (CE) subtype, and 13 (35.1%, 3/37) small artery occlusion (SAO) subtype, according to TOAST classification. In the acute phase, the IS patients presented with NIHSS 4 (interquartile range: 1, 10). Multi-infarction was more common than single infarction (72.7 vs. 27.3%), while cortical + subcortical infarction (CE group: 50%) or subcortical infarction (SAO group: 53.8%) constituted most IS cases. Additionally, the blood supply areas of anterior circulation (CE group: 45.5%; SAO group: 92.3%) or anterior + posterior circulation (CE group: 50%) were mainly involved. The 1-year survival rate of HCM patients with concomitant IS was 81.8%, and IS was associated with 1-year all-cause death in HCM patients (HR = 5.689, 95% CI: 1.784-18.144, p = 0.003).

Conclusion

Older age is a risk factor for IS occurrence in HCM patients. Patients with HCM complicated by IS had mild or moderate neurologic deficits at disease onset. CE and SAO subtypes predominate in patients with concomitant IS, especially the former. Multiple cortical and subcortical infarctions are their neuroimaging characteristics, mainly involving the anterior circulation or anterior + posterior circulation. Is is a risk factor for all-cause death in HCM patients within 1 year.

Prognostic significance of serum alkaline phosphatase for all-cause mortality in patients with hypertrophic cardiomyopathy: A cohort of the hospitalized population

Higher levels of serum alkaline phosphatase (ALP) as a novel risk factor was recently found associated with mortality in different population, whereas, the relationship remains unknown in hypertrophic cardiomyopathy (HCM) population. In this study, we hypothesized that increased ALP could predict all-cause mortality in the adult HCM population. In this cohort study, retrospective data from 538 HCM patients consecutively recruited in West China Hospital were collected. Patients were divided into two groups by baseline ALP with 80 IU/L as the cutoff. All-cause mortality was set as the endpoint. Subgroup analysis was conducted in patients with normal liver function. In total, 461 adult HCM patients were included. After a median follow-up of 4.7 years, 91 patients died. Alkaline phosphatase was an independent predictor of all-cause mortality since patients in the higher ALP group had an increased risk (adjusted HR 2.0, 95% CI: 1.3-3.3, P < 0.01) compared with those in the lower ALP group. In subgroup analysis, the relationship was consistent with the overall (adjusted HR: 3.0, 95% CI: 1.7-5.3, P < 0.01 for the higher ALP group). In the Chinese cohort study of HCM patients, serum ALP is independently associated with all-cause mortality. Patients with a measured value above 80 IU/L had an increased risk of all-cause mortality and this cutoff might help with risk stratification in HCM population.