Follow-up by cardiac magnetic resonance imaging in patients with hypertrophic cardiomyopathy who underwent percutaneous ventricular septal ablation

Alcohol Septal Ablation in Patients with Hypertrophic Obstructive Cardiomyopathy: A Contemporary Perspective

Alcohol septal ablation is a minimally invasive procedure for the treatment of left ventricular outflow tract (LVOT) obstruction in patients with hypertrophic obstructive cardiomyopathy (HOCM) who remain symptomatic despite optimal medical therapy. The procedure causes a controlled myocardial infarction of the basal portion of the interventricular septum by the injection of absolute alcohol with the aim of reducing LVOT obstruction and improving the patient's hemodynamics and symptoms. Numerous observations have demonstrated the efficacy and safety of the procedure, making it a valid alternative to surgical myectomy. In particular, the success of alcohol septal ablation depends on appropriate patient selection and the experience of the institution where the procedure is performed. In this review, we summarize the current evidence on alcohol septal ablation and highlight the importance of a multidisciplinary approach involving a team of clinical and interventional cardiologists and cardiac surgeons with high expertise in the management of HOCM patients-the Cardiomyopathy Team.

Survival Following Alcohol Septal Ablation or Septal Myectomy for Patients With Obstructive Hypertrophic Cardiomyopathy

BACKGROUND

There is little information regarding long-term mortality comparing the 2 most common procedures for septal reduction for obstructive hypertrophic cardiomyopathy (HCM), alcohol septal ablation (ASA), and septal myectomy.

OBJECTIVES

This study sought to compare the long-term mortality of patients with obstructive HCM following septal myectomy or ASA.

METHODS

We evaluated outcomes of 3,859 patients who underwent ASA or septal myectomy in 3 specialized HCM centers. All-cause mortality was the primary endpoint of the study.

RESULTS

In the study cohort, 585 (15.2%) patients underwent ASA, and 3,274 (84.8%) underwent septal myectomy. Patients undergoing ASA were significantly older (median age: 63.0 years [IQR: 52.7-72.8 years] vs 53.7 years [IQR: 44.9-62.8 years]; P < 0.001) and had smaller septal thickness (19.0 mm [IQR: 17.0-22.0 mm] vs 20.0 mm [IQR: 17.0-23.0 mm]; P = 0.007). Patients undergoing ASA also had more comorbidities, including renal failure, diabetes, hypertension, and coronary artery disease. There were 4 (0.7%) early deaths in the ASA group and 9 (0.3%) in the myectomy group. Over a median follow-up of 6.4 years (IQR: 3.6-10.2 years), the 10-year all-cause mortality rate was 26.1% in the ASA group and 8.2% in the myectomy group. After adjustment for age, sex, and comorbidities, the mortality remained greater in patients having septal reduction by ASA (HR: 1.68; 95% CI: 1.29-2.19; P < 0.001).

CONCLUSIONS

In patients with obstructive hypertrophic cardiomyopathy, ASA is associated with increased long-term all-cause mortality compared with septal myectomy. This impact on survival is independent of other known factors but may be influenced by unmeasured confounding patient characteristics.

Short- and long-term outcome after alcohol septal ablation in obstructive hypertrophic cardiomyopathy: Experience of a reference center

INTRODUCTION

In obstructive hypertrophic cardiomyopathy (HCM), alcohol septal ablation (ASA) can lead to gradient reduction and symptom improvement. We aimed to assess the efficacy and safety of ASA in a long-term outcome study.

METHODS

We analyzed patients who underwent ASA over a seven-year period in a tertiary center. The primary echocardiographic endpoint was >50% reduction in left ventricular outflow tract (LVOT) gradient within a year of the procedure. The primary clinical endpoints were improvement in functional capacity and a combined endpoint of cardiac death and rehospitalization for cardiac cause. The follow-up period was 4.17±2.13 years.

RESULTS

A total of 80 patients, mean age 63.9±12.3 years, 30.0% male, were analyzed. Baseline LVOT gradient was 96.3±34.6 mmHg and interventricular septal thickness was 21.6±3.1 mm. Minor complications were observed in 6.3% and major complications in 2.5%, and 8.8% received a permanent pacemaker. The primary echocardiographic endpoint was achieved by 85.7%. At three-month follow-up, LVOT gradient was 25.8±26.0 mmHg in the successful procedure group, compared to 69.2±35.6 mmHg in the other patients (p=0.001). At six months, LVOT gradient was 27.1±27.4 vs. 58.2±16.6 mmHg (p=0.024). Among 74 patients in NYHA class III/IV before the procedure, 57 (77%) improved to NHYA class I/II. The combined primary clinical endpoint (cardiac death and rehospitalization for cardiac cause) was observed in 27.5% (n=22). In the unsuccessful group, the combined endpoint was observed in 54.5%, compared to only 22.7% in the successful group. Only two patients died of cardiac causes.

CONCLUSION

ASA is a safe procedure with a high success rate. Patients who achieved significant reductions in LVOT gradient suffered less cardiac death and rehospitalization for cardiac cause.

Procedural complication and long term outcomes after alcohol septal ablation in patients with obstructive hypertrophic cardiomyopathy: data from China

Data on procedural complications and long term survival after alcohol septal ablation (ASA) in Chinese patients with obstructive hypertrophic cardiomyopathy (HOCM) are lacking. We aimed to investigate long-term survival of HOCM patients after ASA and compared to the non-obstructive hypertrophic cardiomyopathy(NOHCM). A total of 233 patients with HOCM and a peak pressure gradient of ≥50 mm Hg at rest or with provocation were consecutively enrolled from Fuwai Hospital in China between 2000 and 2012. Another 297 patients without left ventricular outflow tract obstruction were regarded as control group. Periprocedural mortality of ASA were low (0.89%). Periprocedural lethal ventricular arrhythmia occurred in 9 patients (4.0%). Alcohol volume (RR 1.44, 95% CI: 1.03–2.03, P = 0.034) and age ≤40 years old (RR 4.63, 95% CI: 1.07–20.0, P = 0.040) were independent predictors for periprocedural lethal ventricular arrhythmia. The 10- year overall survival was 94.6% in the ASA group, similar with 92.9% in the NOHCM group (P = 0.930). In conclusion, periprocedural mortality and complications were rare in ASA. Long term survival after ASA were satisfactory and comparable to NOHCM. Patients under 40 years old should be more cautious undergoing ASA, for these patients were more likely to endure lethal ventricular arrhythmia during periprocedural period of ASA.

Effectiveness of Alcohol Septal Ablation Versus Transaortic Extended Myectomy in Hypertrophic Cardiomyopathy with Midventricular Obstruction

OBJECTIVES

Investigate the effectiveness of alcohol septal ablation (ASA) and transaortic extended myectomy (TEM) in hypertrophic cardiomyopathy (HCM) with midventricular obstruction (MVO).

BACKGROUND

MVO is less common than subaortic obstruction. Data on the effectiveness of ASA and TEM in MVO are lacking.

METHODS

The clinical profiles of 22 patients undergoing ASA and 37 patients undergoing TEM were compared. No patient had apical aneurysm, abnormal chordae, mitral valve replacement or repair.

RESULTS

Baseline midventricular pressure gradient and symptoms were comparable between the ASA and TEM groups. During follow-up, both groups demonstrated substantial reduction in pressure gradient (the ASA group: 79.7 ± 21.2 mm Hg to 43.7 ± 28.9 mm Hg, P < 0.001; the TEM group: 69.0 ± 23.9 mm Hg to 15.0 ± 16.9 mm Hg, P < 0.001). The reduction in pressure gradient was greater (78.9 ± 18.6% vs. 46.4 ± 33.4%, P < 0.001) and the residual pressure gradient was lower after TEM versus ASA (P < 0.001). Patients with New York Heart Association class III/IV dyspnea decreased from 59.1 to 18.2% (P = 0.022) in the ASA group and from 56.8 to 5.6% (P < 0.001) in the TEM group. Patients with Canadian Cardiovascular Society class III/IV angina decreased from 40.9 to 9.1% (P = 0.016) in the ASA group and from 32.4 to 0% (P < 0.001) in the TEM group.

CONCLUSIONS

While ASA and TEM both improve gradients and symptoms, TEM may provide a more reliable reduction in gradients compared to ASA.

Impact of cardiac magnetic resonance imaging in non-ischemic cardiomyopathies

Non-ischemic cardiomyopathies include a wide spectrum of disease states afflicting the heart, whether a primary process or secondary to a systemic condition. Cardiac magnetic resonance imaging (CMR) has established itself as an important imaging modality in the evaluation of non-ischemic cardiomyopathies. CMR is useful in the diagnosis of cardiomyopathy, quantification of ventricular function, establishing etiology, determining prognosis and risk stratification. Technical advances and extensive research over the last decade have resulted in the accumulation of a tremendous amount of data with regards to the utility of CMR in these cardiomyopathies. In this article, we review CMR findings of various non-ischemic cardiomyopathies and focus on current literature investigating the clinical impact of CMR on risk stratification, treatment, and prognosis.

Role of multimodality cardiac imaging in the management of patients with hypertrophic cardiomyopathy: an expert consensus of the European Association of Cardiovascular Imaging Endorsed by the Saudi Heart Association

Taking into account the complexity and limitations of clinical assessment in hypertrophic cardiomyopathy (HCM), imaging techniques play an essential role in the evaluation of patients with this disease. Thus, in HCM patients, imaging provides solutions for most clinical needs, from diagnosis to prognosis and risk stratification, from anatomical and functional assessment to ischaemia detection, from metabolic evaluation to monitoring of treatment modalities, from staging and clinical profiles to follow-up, and from family screening and preclinical diagnosis to differential diagnosis. Accordingly, a multimodality imaging (MMI) approach (including echocardiography, cardiac magnetic resonance, cardiac computed tomography, and cardiac nuclear imaging) is encouraged in the assessment of these patients. The choice of which technique to use should be based on a broad perspective and expert knowledge of what each technique has to offer, including its specific advantages and disadvantages. Experts in different imaging techniques should collaborate and the different methods should be seen as complementary, not as competitors. Each test must be selected in an integrated and rational way in order to provide clear answers to specific clinical questions and problems, trying to avoid redundant and duplicated information, taking into account its availability, benefits, risks, and cost.

Basal infarct location but not larger infarct size is associated with a successful outcome after alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy: a cardiovascular magnetic resonance imaging study

Alcohol septal ablation (ASA) is successful in most but not in all patients with obstructive hypertrophic cardiomyopathy (HCM). We therefore sought to investigate the relation between infarct location versus infarct size with outcome after ASA in patients with obstructive HCM. Baseline characteristics, procedural characteristics, and cardiovascular magnetic resonance findings at baseline and 4-6 month follow-up after ASA were analysed in 47 patients with obstructive HCM in a single-center retrospective study. Infarct size was determined using late gadolinium enhancement. Infarct location was divided into "basal infarction" and "distal infarction" based on an optimal cut-of value of the distance from the basal septum to the beginning of the infarction. A "successful" outcome was defined as 80% reduction of the invasive gradient with a post-procedural gradient of <10 mmHg. Basal infarctions (n = 31) compared to distal infarctions (n = 16) were associated with successful outcome (100 vs. 38%, P < 0.001). Larger infarct size (n = 20) compared to smaller infarct size (n = 27) was not associated with successful outcome (75 vs. 82%, P = 0.72). A more distal location of the infarction, was the only predictor of a less successful outcome (odds ratio 0.76, 95% confidence interval 0.54-0.98, P = 0.03). Basal versus distal infarctions were also associated with a lower provoked gradient at late (2.6 ± 2.2 years) follow-up (11 (6-20) vs. 27 (12-94) mmHg, P = 0.01). Basal infarctions were associated with a successful outcome after ASA. A larger infarct size was not associated with a better outcome.

Characteristics of myocardial postsystolic shortening in patients with symptomatic hypertrophic obstructive cardiomyopathy before and half a year after alcohol septal ablation assessed by speckle tracking echocardiography

Objectives

Postsystolic shortening (PSS) has been proposed as a marker of myocardial dysfunction. Percutaneous transluminal septal myocardial ablation (PTSMA) is an alternative therapy for patients with hypertrophic obstructive cardiomyopathy (HOCM) that results in sustained improvements in atrial structure and function. We investigated the effects of PTSMA on PSS in HOCM patients using speckle tracking imaging.

Methods

Conventional echocardiographic and PSS parameters were obtained in 18 healthy controls and 30 HOCM patients before and half a year after PTSMA.

Results

Compared with the healthy controls, the number of segments having PSS and the average value of PSS were significantly increased in the HOCM patients. At 6 months after PTSMA, both the number of segments having PSS (10.5±2.8 vs. 13.2±2.6; P<0.001) and the average value of PSS (−1.24±0.57 vs. −1.55±0.56; P = 0.009) were significantly reduced. Moreover, the reductions in the average value of PSS correlated well with the reductions in the E-to-Ea ratio (r = 0.705, P<0.001).

Conclusions

Both the number of segments having PSS and the average value of PSS were significantly increased in the HOCM patients. PTSMA has a favourable effect on PSS, which may partly account for the persistent improvement in LV diastolic function in HOCM patients after PTSMA.

Evaluation of left ventricular myocardial perfusion and function using gated SPECT in patients with hypertrophic obstruction cardiomyopathy following percutaneous transluminal septal myocardial ablation

OBJECTIVE

This study was designed to evaluate the left ventricular myocardial perfusion and function in hypertrophic obstruction cardiomyopathy patients following percutaneous transluminal septal myocardial ablation (PTSMA) using rest single-photon emission computed tomography (SPECT) myocardial perfusion imaging.

PATIENTS AND METHODS

Thirty-five patients (24 men and 11 women, 48±11 years old) with hypertrophic obstruction cardiomyopathy underwent rest-gated Tc-MIBI SPECT imaging 4±10 days before (baseline) and 4.7±1.0 days (short-term) and 15.5±8.2 months (mid-term) after PTSMA. Semiquantitative and QGS quantitative evaluations of perfusion and function were carried out in 17 left ventricular segments.

RESULTS

Myocardial perfusion of the septum following PTSMA was significantly reduced compared with baseline in all patients (P<0.05), but the myocardial perfusion in the basal septum was significantly higher at mid-term compared with short-term following PTSMA (P<0.05). Left ventricular ejection fraction was significantly decreased following PTSMA (P<0.05). Regional wall motion assessed in the basal anterior, basal septum, and basal inferior areas following PTSMA was significantly reduced compared with baseline (P<0.05), and wall thickening of the interventricular septum was decreased following PTSMA (P<0.05).

CONCLUSION

Rest-gated SPECT imaging can be used to assess left ventricular myocardial perfusion and function and to investigate the efficacy of PTSMA during follow-up.

Green tea halts progression of cardiac transthyretin amyloidosis: an observational report

Background

Treatment options in patients with amyloidotic transthyretin (ATTR) cardiomyopathy are limited. Epigallocatechin-3-gallate (EGCG), the most abundant catechin in green tea (GT), inhibits fibril formation from several amyloidogenic proteins in vitro. Thus, it might also halt progression of TTR amyloidosis. This is a single-center observational report on the effects of GT consumption in patients with ATTR cardiomopathy.

Methods

19 patients with ATTR cardiomyopathy were evaluated by standard blood tests, echocardiography, and cardiac MRI (n = 9) before and after consumption of GT and/or green tea extracts (GTE) for 12 months.

Results

Five patients were not followed up for reasons of death (n = 2), discontinuation of GT/GTE consumption (n = 2), and heart transplantation (n = 1). After 12 months no increase of left ventricular (LV) wall thickness and LV myocardial mass was observed by echocardiography. In the subgroup of patients evaluated by cardiac MRI a mean decrease of LV myocardial mass (−12.5 %) was detected in all patients. This was accompanied by an increase of mean mitral annular systolic velocity of 9 % in all 14 patients. Total cholesterol (191.9 ± 8.9 vs. 172.7 ± 9.4 mg/dL; p < 0.01) and LDL cholesterol (105.8 ± 7.6 vs. 89.5 ± 8.0 mg/dL; p < 0.01) decreased significantly during the observational period. No serious adverse effects were reported by any of the participants.

Conclusions

Our observation suggests an inhibitory effect of GT and/or GTE on the progression of cardiac amyloidosis. We propose a randomized placebo-controlled investigation to confirm our observation.

Electronic supplementary material

The online version of this article (doi:10.1007/s00392-012-0463-z) contains supplementary material, which is available to authorized users.

Clinical utility of cardiovascular magnetic resonance in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is characterized by substantial genetic and phenotypic heterogeneity, leading to considerable diversity in clinical course including the most common cause of sudden death in young people and a determinant of heart failure symptoms in patients of any age. Traditionally, two-dimensional echocardiography has been the most reliable method for establishing a clinical diagnosis of HCM. However, cardiovascular magnetic resonance (CMR), with its high spatial resolution and tomographic imaging capability, has emerged as a technique particularly well suited to characterize the diverse phenotypic expression of this complex disease. For example, CMR is often superior to echocardiography for HCM diagnosis, by identifying areas of segmental hypertrophy (ie., anterolateral wall or apex) not reliably visualized by echocardiography (or underestimated in terms of extent). High-risk HCM patient subgroups identified with CMR include those with thin-walled scarred LV apical aneurysms (which prior to CMR imaging in HCM remained largely undetected), end-stage systolic dysfunction, and massive LV hypertrophy. CMR observations also suggest that the cardiomyopathic process in HCM is more diffuse than previously regarded, extending beyond the LV myocardium to include thickening of the right ventricular wall as well as substantial morphologic diversity with regard to papillary muscles and mitral valve. These findings have implications for management strategies in patients undergoing invasive septal reduction therapy. Among HCM family members, CMR has identified unique phenotypic markers of affected genetic status in the absence of LV hypertrophy including: myocardial crypts, elongated mitral valve leaflets and late gadolinium enhancement. The unique capability of contrast-enhanced CMR with late gadolinium enhancement to identify myocardial fibrosis has raised the expectation that this may represent a novel marker, which may enhance risk stratification. At this time, late gadolinium enhancement appears to be an important determinant of adverse LV remodeling associated with systolic dysfunction. However, the predictive significance of LGE for sudden death is incompletely resolved and ultimately future large prospective studies may provide greater insights into this issue. These observations underscore an important role for CMR in the contemporary assessment of patients with HCM, providing important information impacting diagnosis and clinical management strategies.