Sustained ventricular tachycardia in apical hypertrophic cardiomyopathy, midcavitary obstruction, and apical aneurysm

Clinical Outcomes After the Surgical Treatment of Hypertrophic Obstructive Cardiomyopathy With Left Ventricular Apical Aneurysm

BACKGROUND

Left ventricular apical aneurysm (LVAA) is a rare complication of hypertrophic obstructive cardiomyopathy (HOCM). This study aimed to illustrate the clinical characteristics and surgical outcomes of these patients.

METHOD

Patients with HOCM and LVAA who underwent modified extended Morrow myectomy and surgical left ventricular reconstruction (SLVR) between October 2012 and March 2021 were retrospectively recruited. Patients with coronary artery disease were excluded. Clinical characteristics were summarised. Time-to-event outcomes were calculated using the Kaplan-Meier method and compared by a log-rank test.

RESULTS

Fifteen eligible patients were identified; the mean age was 39.9±17.2 years and 40.0% of them were female. All patients had dyspnoea, 46.7% presented with syncope and/or chest pain, and 13.3% had a family history of hypertrophic cardiomyopathy. The mean LVAA size was 36.9±12.3 mm in length and 28.5±11.3 mm in width. Echocardiography showed LV outflow tract obstruction in seven (46.7%) patients, mid-cavity LV obstruction in 12 (80.0%), while systolic anterior motion (SAM) was seen in seven (46.7%). The symptoms were resolved in all patients postoperatively. During a median follow-up of 22.0 months, one (6.7%) patient had sudden cardiac death, one (6.7%) had a haemorrhagic stroke, and the LVAA recurrence was 40.0%. Subgroup analysis showed that signs of SAM and larger LVAA (≥30 mm) were associated with an increased tendency for a longer hospital stay.

CONCLUSIONS

Patients with HOCM and LVAA present with high-risk profiles. Modified extended Morrow myectomy combined with SLVR is useful in relieving the symptoms and improving the prognosis, although there might be recurrent LVAA.

Ventricular fibrillation and sudden cardiac arrest in apical hypertrophic cardiomyopathy: Two case reports

BACKGROUND

Apical hypertrophic cardiomyopathy (HCM) is considered to have a benign prognosis in terms of cardiovascular mortality. This serial case report aimed to raise awareness of ventricular fibrillation (VF) and sudden cardiac death (SCD) in apical HCM.

CASE SUMMARY

Here we describe two rare cases of apical HCM that presented with documented VF and sudden cardiac collapse. These patients were previously not recommended for primary prevention using implantable cardioverter-defibrillator (ICD) therapy based on current guidelines. However, both received ICD therapy for the secondary prevention of SCD.

CONCLUSION

These cases illustrate serious complications including VF and aborted sudden cardiac arrest in apical HCM patients who are initially not candidates for primary prevention using ICD implantation based on current guidelines.

Mid-ventricular obstruction is associated with non-sustained ventricular tachycardia in patients with hypertrophic obstructive cardiomyopathy

Background

Mid‐ventricular obstruction (MVO) is a rare subtype of hypertrophic cardiomyopathy (HCM) but it is associated with ventricular arrhythmia. The relationship between MVO and non‐sustained ventricular tachycardia (NSVT) in HCM patients is unknown.

Hypothesis

The severity of MVO increases the incidence of NSVT in patients with hypertrophic obstructive cardiomyopathy (HOCM).

Methods

Five hundred and seventy‐two consecutive patients diagnosed with HOCM in Fuwai Hospital between January 2015 and December 2017 were enrolled in this study. Holter electrocardiographic and clinical parameters were compared between HOCM patients with and without MVO.

Results

Seventy‐six (13.3%) of 572 patients were diagnosed with MVO. Compared to patients without MVO, those with MVO were much younger, and had a higher incidence of syncope, greater left ventricular (LV) posterior wall thickness, a higher percentage of LV late gadolinium enhancement, and higher prevalence of NSVT. Furthermore, the prevalence of NSVT increased with the severity of MVO (without, mild, moderate or severe: 11.1%, 18.2%, 25.6%, respectively, p for trend < .01). Similarly, the prevalence of NSVT differed among patients with isolated LV outflow tract (LVOTO), both MVO and LVOTO, and isolated MVO (11.1%, 21.3%, 26.6%, respectively, p for trend = .018). In addition to age, diabetes, left atrial diameter, and maximal wall thickness, multivariate analysis revealed the presence of MVO as an independent risk factor for NSVT (Odds ratio 2.69; 95% confidence interval 1.41 to 5.13, p = .003).

Conclusions

The presence and severity of MVO was associated with higher incidence of NSVT in HOCM patients.

The evolution of apical hypertrophic cardiomyopathy: Development of mid-ventricular obstruction and apical aneurysm 11 years after initial diagnosis

Asian hypertrophic cardiomyopathy (AHCM) is a rare variant of hypertrophic cardiomyopathy (HCM) that is more prevalent in the Asian population. There is significant overlap between AHCM, mid-cavitary obstruction, and apical aneurysms. Although more benign compared to HCM, the course of AHCM is not clearly defined. We present an interesting case of an African American male with known AHCM who develops symptomatic mid-cavitary obstruction and apical aneurysm 11 years after initial diagnosis.

Ventricular Fibrillation Cardiac Arrest in African American Male with Apical Hypertrophic Cardiomyopathy

Apical hypertrophic cardiomyopathy (AHCM) is a rare form of non-obstructive hypertrophic cardiomyopathy. It is rarely reported in African American patients, and more commonly reported in Japanese patients. AHCM involves hypertrophy of the apex of the left ventricle. It is considered to have a benign prognosis in terms of cardiovascular mortality, however arrhythmias and sudden cardiac death have been reported. We report a case of a 49-year-old African American male with a history of hypertension, who presented to the emergency department after in field defibrillation for ventricular fibrillation cardiac arrest with return of spontaneous circulation after 10 minutes of cardiopulmonary resuscitation. Features of left ventricular hypertrophy and deep T-wave inversions in V3-V6 were noted on a 12-lead electrocardiogram which were suggestive of AHCM. Left heart catheterization with left ventriculography and coronary angiography confirmed the diagnosis of AHCM with the classic “ace of spades” sign. This case highlights the rare occurrence of AHCM with ventricular fibrillation cardiac arrest in an African American male, treated with hypertension management, aspirin, atorvastatin and automated implantable cardioverter-defibrillator placement.

Yamaguchi syndrome presenting as atrioventricular nodal re-entrant tachycardia in an African-American patient

Apical hypertrophic cardiomyopathy (Yamaguchi syndrome) is a rare subtype of hypertrophic cardiomyopathy. The syndrome is more common in Japan where it was first described. Outside Asia, it is a very rare cause of hypertrophic cardiomyopathy. Apical hypertrophic cardiomyopathy is usually detected incidentally and has a good long-term outcome. We present a case of apical hypertrophic cardiomyopathy in an African-American patient manifesting as atrioventricular nodal re-entrant tachycardia.

Association of ST elevation with apical aneurysm in hypertrophic cardiomyopathy

OBJECTIVES

Apical aneurysms in patients with hypertrophic cardiomyopathy (HCM) represent an underrecognized but clinically important subset of HCM patients. However it may be frequently missed by echocardiography because of poor image quality of left ventricular apex. We aimed to compare electrocardiographic STE in HCM patients with and without apical aneurysm.

METHODS

We developed this clinical review using an extensive MEDLINE review of the literature and data from our laboratories; and some electrocardiographic parameters including STE were analysed in HCM patients with and without apical aneurysm.

RESULTS

There were 29 HCM patients without apical aneurysm (Group 1; 52.6±17.7years, 69% male) and 28 HCM patients with apical aneurysm (Group 2; 59.6±13.2years, 57% male). The STE in V4-6 derivations were statistically more frequent in patients with apical aneurysm compared to those without aneurysm (93% vs 7%, p<0.001). There was a positive correlation between the presence of the STE in V4-6 derivations and the presence of the apical aneurysm (Spearman's ρ=0.895, p<0.001).

CONCLUSIONS

Clinicians and specifically echocardiographers must pay special attention on the electrocardiography to correctly detect the frequently overlooked apical aneurysm in HCM patients, and should be careful for apical aneurysm particularly in the presence of STE in V4-6 derivations.

Ventricular tachycardia in repaired double chambered right ventricle - identification of the substrate and successful ablation

A 35 year old female presented with recurrent ventricular tachycardia 5 years after she had undergone surgical repair of double chambered right ventricle. Electroanatomical mapping showed a localised scar in the apex with double potentials and good pace map. Ablation here resulted in non-inducibility of ventricular tachycardia. We hypothesise that the scarring in the apex is the result of sustained pressure overload and becomes arrhythmogenic similar to the apical scar in patients with mid-ventricular hypertrophic cardiomyopathy.

Apical hypertrophic cardiomyopathy presenting as recurrent unexplained syncope

Apical hypertrophic cardiomyopathy (AHC) is a rare variant of hypertrophic cardiomyopathy. Since its description by Sakamoto in 1976 in Japanese patients, our understanding of this entity has evolved. Although cardiac magnetic resonance imaging has emerged as the gold standard for diagnosing AHC, clinical attention must be drawn to the unique electrocardiographic features that provide the initial clues to making the diagnosis. In this case, we present a 47-year-old man with AHC who presented with recurrent syncope, but anomalies on his electrocardiogram went unnoticed on two clinical encounters. He was subsequently admitted to our service and rapidly diagnosed after we observed the very classical findings in the plain twelve lead electrocardiogram done at the time of admission. In a clinical encounter involving a patient presenting with recurrent syncope, special attention must be focused on the electrocardiogram to decipher the unique diagnostic features it might show.

Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy is a myocardial disease characterized by myocardial hypertrophy, disorganization of cardiac myocytes, and fibrosis. Twenty-five percent of patients have a dynamic left ventricular outflow tract gradient caused by the combined effects of rapid ventricular ejection, a narrowed outflow tract, and systolic anterior motion of the mitral valve. Most cases are caused by mutations in genes that encode cardiac sarcomeric proteins. Patients present at all ages with chest pain, dyspnea, palpitations, and syncope. The most important complications of the disease are sudden cardiac death, heart failure, and thromboembolism. The principal aims of management are the alleviation of symptoms and the prevention of sudden death. In patients with substantial left ventricular outflow tract obstruction, interventions that reduce the magnitude of the outflow tract gradient (disopyramide, verapamil, β-blockade, alcohol ablation of the interventricular septum, dual-chamber pacing, and surgery) often improve symptoms. Therapeutic options in patients without left ventricular outflow tract obstruction are more limited. Clinical risk stratification is used to estimate the risk of sudden death and to target effective prophylactic treatment with an implantable cardioverter defibrillator.