Biventricular / left ventricular pacing in hypertrophic obstructive cardiomyopathy: an overview

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant inherited genetic disease characterized by compensatory pathological left ventricle (LV) hypertrophy due to sarcomere dysfunction. In an important proportion of patients with HCM, the site and extent of cardiac hypertrophy results in severe obstruction to LV outflow tract (LVOT), contributing to disabling symptoms and increasing the risk of sudden cardiac death (SCD). In patients with progressive and/or refractory symptoms despite optimal pharmacological treatment, invasive therapies that diminish or abolish LVOT obstruction relieve heart failure-related symptoms, improve quality of life and could be associated with long-term survival similar to that observed in the general population. The gold standard in this respect is surgical septal myectomy, which might be supplementary associated with a reduction in SCD. Percutaneous techniques, particularly alcohol septal ablation (ASA) and more recently radiofrequency (RF) septal ablation, can achieve LVOT gradient reduction and symptomatic benefit in a large proportion of HOCM patients at the cost of a supposedly limited septal myocardial necrosis and a 10-20% risk of chronic atrioventricular block. After an initial period of enthusiasm, standard DDD pacing failed to show in randomized trials significant LVOT gradient reductions and objective improvement in exercise capacity. However, case reports and recent small pilot studies suggested that atrial synchronous LV or biventricular (biV) pacing significantly reduce LVOT obstruction and improve symptoms (acutely as well as long-term) in a large proportion of severely symptomatic HOCM patients not suitable to other gradient reduction therapies. Moreover, biV/LV pacing in HOCM seems to be associated with significant LV reverse remodelling.     

Pregnancy in women with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is increasingly being diagnosed in pregnant women. Women with HCM generally tolerate pregnancy well. The risk is however higher in women who are symptomatic before pregnancy or in those with severe left ventricular outflow tract obstruction. The incidence of arrhythmias does not appear to be increased during pregnancy and maternal mortality is low. Prior to conception, women with HCM should have a risk assessment as well as genetic counselling. During pregnancy beta-blockers should be continued and the judicious use of diuretics may be required to treat symptoms of dyspnoea. A vaginal delivery with regional anaesthesia is usually appropriate. Women should be managed by a specialist multidisciplinary team.     

Life-long tailoring of management for patients with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common genetic heart disease, characterised by complex pathophysiology and extensive genetic and clinical heterogeneity. In most patients, HCM is caused by mutations in cardiac sarcomere protein genes and inherited as an autosomal dominant trait. The clinical phenotype ranges from severe presentations at a young age to lack of left ventricular hypertrophy in genotype-positive individuals. No preventative treatment is available as the sequence and causality of the pathomechanisms that initiate and exacerbate HCM are unknown. Sudden cardiac death and end-stage heart failure are devastating expressions of this disease. Contemporary management including surgical myectomy and implantable cardiac defibrillators has shown significant impact on long-term prognosis. However, timely recognition of specific scenarios – including transition to the end-stage phase – may be challenging due to limited awareness of the progression patterns of HCM. This in turn may lead to missed therapeutic opportunities. To illustrate these difficulties, we describe two HCM patients who progressed from the typical hyperdynamic stage of asymmetric septal thickening to end-stage heart failure with severely reduced ejection fraction. We highlight the different stages of this complex inherited cardiomyopathy based on the clinical staging proposed by Olivotto and colleagues. In this way, we aim to provide a practical guide for clinicians and hope to increase awareness for this common form of cardiac disease.     

Undiagnosed hypertrophic obstructive cardiomyopathy during transcatheter aortic valve replacement: a case report

Background

Transcatheter aortic valve replacement is indicated for severe symptomatic aortic stenosis in patients who have a very high or prohibitive surgical risk as assessed pre-procedurally by the Society of Thoracic Surgery Risk Score, EuroSCORE (II), frailty testing, and other predictors. When combined with another left ventricular outflow tract obstruction, careful consideration must be taken prior to proceeding with transcatheter aortic valve replacement because an additional masked left ventricular outflow tract pathology can lead to challenging hemodynamics in the peri-deployment phase, as reported in this case.

Case presentation

A 56-year-old Caucasian man with multiple comorbidities and severe aortic stenosis underwent transcatheter aortic valve replacement under monitored anesthesia care. During the deployment phase, he developed dyspnea that progressed to pulmonary edema requiring emergent conversion to general anesthesia, orotracheal intubation, acute respiratory distress syndrome-type ventilation, and vasopressor medications. Intraoperative transesophageal echocardiography was performed and hypertrophic obstructive cardiomyopathy with systolic anterior motion of the mitral valve was discovered as an underlying pathology, undetected on preoperative imaging. After treatment with beta blockers, fluid resuscitation, and alpha-1 agonists, he stabilized and was eventually discharged from our hospital without any lasting sequelae.

Conclusions

Patients with aortic stenosis most often develop symmetric hypertrophy; however, a small subset has asymmetric septal hypertrophy leading to left ventricular outflow tract obstruction. In cases of severe aortic stenosis, however, evidence of left ventricular outflow tract obstruction via both symptoms and echocardiographic findings may be minimized due to extremely high afterload on the left ventricle. Diagnosing a left ventricular outflow tract obstruction as the cause of hemodynamic instability during transcatheter aortic valve replacement, in the absence of abnormal findings on echocardiogram preoperatively, requires a high index of clinical suspicion. The management of acute onset left ventricular outflow tract obstruction intraoperatively consists primarily of medical therapy, including rate control, adequate volume resuscitation, and avoidance of inotropes. With persistently elevated gradients, interventional treatments may be considered.

     

Obstructive hypertrophic cardiomyopathy is associated with reduced expression of vinculin in the intercalated disc

Mutations in the cardiac-specific insert of vinculin, metavinculin, rarely cause hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM). Subsequently, a missense mutation in the ubiquitously expressed vinculin was discovered in a patient with obstructive HCM. Microscopic examination of both myectomy specimens from patients bearing genetic defects in metavinculin and vinculin showed a marked reduction of vinculin/metavinculin expression in the intercalated disc, but normal expression in the Z-disc. Given that distinct functional domains were altered by the metavinculin and vinculin mutations, we hypothesized that the intercalated disc-specific reduction of vinculin may stem from left ventricular tract obstruction in general rather than rarely observed perturbations in VCL-encoded vinculin. To test this hypothesis, we examined the localization of vinculin/metavinculin in hypertrophied human heart tissue from patients with cardiovascular conditions associated with obstruction and hemodynamic overload using an immunohistochemistry approach. Tissue specimens derived from patients with obstructive HCM and aortic stenosis (AS) showed a universal defect of vinculin/metavinculin expression in the intercalated disc but preserved expression in the cardiac Z-disc, whereas tissue specimens derived from patients with either DCM, hypertensive heart disease (HTN), or pulmonary hypertension (PHTN) exhibited normal expression of vinculin/metavinculin in both the Z- and the intercalated disc despite being associated with hypertrophy. Results of this study suggest that cardiac hypertrophy may be associated with different expression of the marker vinculin/metavinculin depending on the underlying pathophysiology; hemodynamic overload may not affect the localization whereas obstructive disease substantially reduces the expression of vinculin preferentially in the intercalated disc.     

Female Sex Is Associated with Worse Prognosis in Patients with Hypertrophic Cardiomyopathy in China

Background

Sex plays an important role in the clinical expression and prognosis of various cardiovascular diseases. This study was designed to observe the effects of sex on hypertrophic cardiomyopathy (HCM).

Methods and Results

A total of 621 unrelated patients with HCM without heart failure (460 males) were enrolled from 1999 to 2011. Compared to male patients, at baseline female patients were older at diagnosis (49.6±17.2 years vs. 46.7±14.4 years, P = 0.033), and had greater frequency of left ventricular outflow tract obstruction (72/161, 44.7% vs. 149/460, 32.4%, P = 0.005). During the average four year follow-up period (range 2–7 years), survival analysis showed that the incidences of mortality from all causes, cardiovascular death and progression to chronic heart failure were greater in women than in men (P = 0.031, 0.040 and 0.012, respectively). After adjustment for multiple factors that may confound survival and cardiac function, female sex remained an independent risk factor for all-cause mortality, cardiovascular death, and chronic heart failure [hazard ratio (HR) 2.19, 95% confidence interval (CI) 1.21–3.95, P = 0.010; HR 2.19, 95% CI 1.17–4.09, P = 0.014; HR 1.73, 95% CI 1.12–2.69, P = 0.014, respectively] in HCM patients. Subgroup analysis revealed that female sex as a risk factor was identified only in patients younger than 50 years old (P = 0.011, 0.011 and 0.009, respectively), but not for those 50 years or older.

Conclusion

Our results suggest that female sex is associated with worse survival and heart failure in HCM patients. Further studies are required to determine whether female hormones modify the clinical expression and prognosis of HCM.     

Clinical Use of a New Mitral Disc Valve

A disc valve of new design was used successfully for the replacement of the mitral valve in patients with rheumatic mitral valve disease. This valve would appear to have the following advantages over the mitral ball valve prosthesis:• Lower left atrial pressure after replacement.• Elimination of the hazard of left ventricular outflow tract obstruction with mitral valve replacement.• Decreased incidence of thromboembolization.• Abolition of possibility of ventricular septal irritation.Despite the better outlook for this valve compared with the ball valve for mitral valve substitution, the mitral valve should always be repaired whenever feasible. Repair is possible in the majority of patients.     

Coronary flow reserve in hypertrophic cardiomyopathy: relation with microvascular dysfunction and pathophysiological characteristics

Background. The decrease in coronary flow reserve (CFR) in hypertrophic cardiomyopathy (HCM) predisposes to myocardial ischaemia, systolic dysfunction and cardiac death. In this study we investigate to which extent haemodynamic, echocardiographic, and histological parameters contribute to the reduction of CFR. Methods. In ten HCM patients (mean age 44±14 years) and eight heart transplant (HTX) patients (mean age 51±6 years) CFR was calculated in the left anterior descending coronary artery. In all subjects haemodynamic, echocardiographic and histological parameters were assessed. The relationship between these variables and CFR was determined using linear regression analysis. Results. CFR was reduced in HCM compared with HTX patients (1.6±0.7 vs. 2.7±0.8, p<0.01). An increase in septal thickness (p<0.005), indexed left ventricular (LV) mass (p<0.005), LV end-diastolic pressure (p<0.001), LV outflow tract gradient (p<0.05) and a decrease in arteriolar lumen size (p<0.05) were all related to a reduction in CFR. Conclusion: In HCM patients haemodynamic (LV end-diastolic pressure, LV outflow tract gradient), echocardiographic (indexed LV mass) and histological (% luminal area of the arterioles) changes are responsible for a decrease in CFR. (Neth Heart J 2007;15:209-15.)     

Fibroblast Growth Factor Receptor 1 Signaling in Adult Cardiomyocytes Increases Contractility and Results in a Hypertrophic Cardiomyopathy

Fibroblast growth factors (FGFs) and their receptors are highly conserved signaling molecules that have been implicated in postnatal cardiac remodeling. However, it is not known whether cardiomyocyte-expressed FGF receptors are necessary or sufficient for ventricular remodeling in the adult heart. To determine whether cardiomyocytes were competent to respond to an activated FGF receptor, and to determine if this signal would result in the development of hypertrophy, we engineered a doxycycline (DOX)-inducible, cardiomyocyte-specific, constitutively active FGF receptor mouse model (αMHC-rtTA, TRE-caFgfr1-myc). Echocardiographic and hemodynamic analysis indicated that acute expression of caFGFR1 rapidly and directly increased cardiac contractility, while chronic expression resulted in significant hypertrophy with preservation of systolic function. Subsequent histologic analysis showed increased cardiomyocyte cross-sectional area and regions of myocyte disarray and fibrosis, classic features of hypertrophic cardiomyopathy (HCM). Analysis of downstream pathways revealed a lack of clear activation of classical FGF-mediated signaling pathways, but did demonstrate a reduction in Serca2 expression and troponin I phosphorylation. Isolated ventricular myocytes showed enhanced contractility and reduced relaxation, an effect that was partially reversed by inhibition of actin-myosin interactions. We conclude that adult cardiomyocytes are competent to transduce FGF signaling and that FGF signaling is sufficient to promote increased cardiomyocyte contractility in vitro and in vivo through enhanced intrinsic actin-myosin interactions. Long-term, FGFR overexpression results in HCM with a dynamic outflow tract obstruction, and may serve as a unique model of HCM.     

ENerGetIcs in hypertrophic cardiomyopathy: traNslation between MRI, PET and cardiac myofilament function (ENGINE study)

Introduction

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant heart disease mostly due to mutations in genes encoding sarcomeric proteins. HCM is characterised by asymmetric hypertrophy of the left ventricle (LV) in the absence of another cardiac or systemic disease. At present it lacks specific treatment to prevent or reverse cardiac dysfunction and hypertrophy in mutation carriers and HCM patients. Previous studies have indicated that sarcomere mutations increase energetic costs of cardiac contraction and cause myocardial dysfunction and hypertrophy. By using a translational approach, we aim to determine to what extent disturbances of myocardial energy metabolism underlie disease progression in HCM.

Methods

Hypertrophic obstructive cardiomyopathy (HOCM) patients and aortic valve stenosis (AVS) patients will undergo a positron emission tomography (PET) with acetate and cardiovascular magnetic resonance imaging (CMR) with tissue tagging before and 4 months after myectomy surgery or aortic valve replacement + septal biopsy. Myectomy tissue or septal biopsy will be used to determine efficiency of sarcomere contraction in-vitro, and results will be compared with in-vivo cardiac performance. Healthy subjects and non-hypertrophic HCM mutation carriers will serve as a control group.

Endpoints

Our study will reveal whether perturbations in cardiac energetics deteriorate during disease progression in HCM and whether these changes are attributed to cardiac remodelling or the presence of a sarcomere mutation per se. In-vitro studies in hypertrophied cardiac muscle from HOCM and AVS patients will establish whether sarcomere mutations increase ATP consumption of sarcomeres in human myocardium. Our follow-up imaging study in HOCM and AVS patients will reveal whether impaired cardiac energetics are restored by cardiac surgery.     

改良Nikaidoh手术治疗合并肺动脉瓣狭窄的右室双出口

目的：总结改良Nikaidoh手术治疗右心室双出口（DORV）患者的临床经验,以提高手术疗效。方法：2例先天性心脏病右心室双出口伴肺动脉瓣狭窄行改良Nikaidoh手术,游离主动脉根部及冠状动脉,重建左心室流出道,以带单瓣牛心包片补片重建肺动脉及右心室流出道。结果：术后患者紫绀消失,复查心脏彩超仅有轻度肺动脉瓣关闭不全,未发现左、右心室流出道梗阻,康复出院。结论：采用改良Nikaidoh手术治疗伴肺动脉瓣狭窄的右室双出口,术后可获得良好的血流动力学效果,早期临床结果满意。     

肥厚梗阻性心肌病的外科治疗

目的:总结肥厚室间隔切除术治疗肥厚梗阻性心肌病的手术效果,探讨外科治疗策略。方法:2002年3月至2010年10月,外科手术治疗33例肥厚梗阻性心肌病病人。其中男16例,女17例;年龄13～59岁,平均(42.7±13.6)岁;左室流出道压差(LVOTGP)70～120 mmHg(1 mmHg=0.133Kpa),平均(95.0±22.6)mmHg。其中合并二尖瓣关闭不全24例,主动脉瓣关闭不全7例,升主动脉增宽3例,冠心病2例。手术在全麻低温体外循环下完成,按常规经主动脉切口行室间隔心肌切除术,同期完成二尖瓣置换术(MVR)7例,二尖瓣成形术(MVP)7例,二尖瓣、主动脉瓣成形术(MVP+AVP)5例,二尖瓣、升主动脉成形术3例,二尖瓣、主动脉瓣成形、冠状动脉旁路移植术(MVP+AVP+CABG)2例。分析比较病人术前超声心动图(UCG),术中经食管心脏超声(TEE),以及术后1周、3月、6月、1年超声心动图结果。结果:手术死亡1例(3.0%,1/33例),主要死因为严重低心排综合症以及多脏器功能衰竭。二次开胸止血1例(3.0%,1/33例)。术中经食管心脏超声示所有病人二尖瓣前叶收缩期前向运动现象(SAM征)消失。存活病人手术效果良好,解剖狭窄解除,峰值压差降低,SAM现象基本消失。远期随访生存病人症状消失,生活质量明显改善,心功能I～II级,无远期死亡、并发症或再次手术。结论:外科治疗肥厚梗阻型心肌病具有良好的手术效果。了解病生理过程、术中仔细探察、手术切除彻底是手术成功的关键。     

In Hypertrophic Cardiomyopathy Reduction of Relative Resting Myocardial Blood Flow Is Related to Late Enhancement, T2-Signal and LV Wall Thickness

Objectives

To quantify resting myocardial blood flow (MBF) in the left ventricular (LV) wall of HCM patients and to determine the relationship to important parameters of disease: LV wall thickness, late gadolinium enhancement (LGE), T2-signal abnormalities (dark and bright signal), LV outflow tract obstruction and age.

Materials and Methods

Seventy patients with proven HCM underwent cardiac MRI. Absolute and relative resting MBF were calculated from cardiac perfusion MRI by using the Fermi function model. The relationship between relative MBF and LV wall thickness, T2-signal abnormalities (T2 dark and T2 bright signal), LGE, age and LV outflow gradient as determined by echocardiography was determined using simple and multiple linear regression analysis. Categories of reduced and elevated perfusion in relation to non- or mildly affected reference segments were defined, and T2-signal characteristics and extent as well as pattern of LGE were examined. Statistical testing included linear and logistic regression analysis, unpaired t-test, odds ratios, and Fisher’s exact test.

Results

804 segments in 70 patients were included in the analysis. In a simple linear regression model LV wall thickness (p<0.001), extent of LGE (p<0.001), presence of edema, defined as focal T2 bright signal (p<0.001), T2 dark signal (p<0.001) and age (p = 0.032) correlated inversely with relative resting MBF. The LV outflow gradient did not show any effect on resting perfusion (p = 0.901). Multiple linear regression analysis revealed that LGE (p<0.001), edema (p = 0.026) and T2 dark signal (p = 0.019) were independent predictors of relative resting MBF. Segments with reduced resting perfusion demonstrated different LGE patterns compared to segments with elevated resting perfusion.

Conclusion

In HCM resting MBF is significantly reduced depending on LV wall thickness, extent of LGE, focal T2 signal abnormalities and age. Furthermore, different patterns of perfusion in HCM patients have been defined, which may represent different stages of disease.     

Microsphere embolisation as an alternative for alcohol in percutaneous transluminal septal myocardial ablation

Background

Percutaneous transluminal septal myocardial ablation using microsphere embolisation is a new interventional technique to treat patients with hypertrophic obstructive cardiomyopathy.

Methods and results

In two patients, considered at high risk for myectomy, targeted septal perforators were occluded with microsphere embolisation instead of alcohol ablation to reduce left ventricular outflow gradient. In both cases the left ventricular outflow tract gradient was immediately reduced. No adverse events occurred.

Conclusion

This is the first clinical experience with Embozene® Microspheres in the Netherlands as an alternative for alcohol septal ablation. In both cases it resulted in immediate improvement in the haemodynamics, without any adverse events.     

Medical therapy versus interventional therapy in hypertropic obstructive cardiomyopathy

Medical treatment in symptomatic patients with hypertrophic obstructive cardiomyopathy aims to reduce the outflow tract gradients, and to improve diastolic dysfunction and rhythm disorders. Surgical myectomy is the standard treatment in patients with drug refractory symptoms. Since the early 1990s, dual-chamber (DDD)-pacemaker implantation and percutaneous transluminal septal myocardial ablation by alcohol-induced septal branch occlusion have widened treatment options in this subgroup of patients. An overview of medical and interventional treatment is presented.     

肥厚梗阻性心肌病的外科治疗

目的：总结肥厚室间隔切除术治疗肥厚梗阻性心肌病的手术效果,探讨外科治疗策略。方法：2002年3月至2010年10月,外科手术治疗33例肥厚梗阻性心肌病病人。其中男16例,女17例;年龄13～59岁,平均（42.7±13.6）岁;左室流出道压差（LVOTGP）70～120 mmHg（1 mmHg=0.133Kpa）,平均（95.0±22.6）mmHg。其中合并二尖瓣关闭不全24例,主动脉瓣关闭不全7例,升主动脉增宽3例,冠心病2例。手术在全麻低温体外循环下完成,按常规经主动脉切口行室间隔心肌切除术,同期完成二尖瓣置换术（MVR）7例,二尖瓣成形术（MVP）7例,二尖瓣、主动脉瓣成形术（MVP＋AVP）5例,二尖瓣、升主动脉成形术3例,二尖瓣、主动脉瓣成形、冠状动脉旁路移植术（MVP＋AVP＋CABG）2例。分析比较病人术前超声心动图（UCG）,术中经食管心脏超声（TEE）,以及术后1周、3月、6月、1年超声心动图结果。结果：手术死亡1例（3.0%,1/33例）,主要死因为严重低心排综合症以及多脏器功能衰竭。二次开胸止血1例（3.0%,1/33例）。术中经食管心脏超声示所有病人二尖瓣前叶收缩期前向运动现象（SAM征）消失。存活病人手术效果良好,解剖狭窄解除,峰值压差降低,SAM现象基本消失。远期随访生存病人症状消失,生活质量明显改善,心功能I～II级,无远期死亡、并发症或再次手术。结论：外科治疗肥厚梗阻型心肌病具有良好的手术效果。了解病生理过程、术中仔细探察、手术切除彻底是手术成功的关键。     

ACS,myocardial bridging,Tako-tsubo syndrome and mitral regurgitation

Isolated systolic compression of the mid portion of the left anterior descending artery (LAD) by a bridge of overlying cardiac muscle is an infrequent but well-recognised angiographic anomaly that is often considered harmless. The long-term prognosis appears to be excellent, but occasional reports of patients with angina pectoris, myocardial infarction and sudden death indicate that this is not always true. The prevalence of the anomaly in the normal population is unknown, but the incidence is low and ischaemic events are rare.Tako-tsubo-like left ventricular dysfunction syndrome (TTS) is characterised by ischaemia, anterior ST-segment elevation, no significant coronary artery disease and reversible ampulla-like left ventricular ballooning in postmenopausal females after emotional or physical stress. Dynamic left ventricular outflow tract (LVOT) obstruction is a rare but potentially fatal complication of acute anterior wall infarction.We present a patient with an acute coronary syndrome (ACS) with ST-segment elevation in the anterior leads, transient TTS and transient LVOT obstruction with systolic anterior motion (SAM) of the mitral valve and severe mitral regurgitation. This is the first report of myocardial bridging associated with TTS, and the first report of TTS associated with dynamic LVOT obstruction with SAM and mitral regurgitation.     

RAAS gene polymorphisms influence progression of pediatric hypertrophic cardiomyopathy

Hypertrophic Cardiomyopathy (HCM) is a disease with variable rate of progression. Young age is an independent risk factor for poor outcome in HCM. The influence of renin–angiotensin–aldosterone (RAAS) genotype on the progression of HCM in children is unknown. Children with HCM (n = 65) were enrolled prospectively across two centers (2001–2005). All subjects were genotyped for five RAAS gene polymorphisms previously associated with LV hypertrophy (pro-LVH): AGT M235T, ACE DD, CMA-1903 A/G, AGTR1 1666 A/C and CYP11B2-344 C/T. Linear regression models, based on maximum likelihood estimates, were created to assess the independent effect of RAAS genotype on LV hypertrophy (LVH). Forty-six subjects were homozygous for <2 and 19 were homozygous for ≥2 pro-LVH RAAS polymorphisms. Mean age at presentation was 9.6 ± 6 years. Forty children had follow-up echocardiograms after a median of 1.5 years. Indexed LV mass (LVMI) and LV mass z-scores were higher at presentation and follow-up in subjects with ≥2 pro-LVH genotypes compared to those with <2 (P < 0.05). Subjects with ≥2 pro-LVH genotypes also demonstrated a greater increase in septal thickness (IVST) and in LV outflow tract (LVOT) obstruction on follow-up (P < 0.05). On multivariate analysis, a higher number of pro-LVH genotypes was associated with a larger effect size (P < 0.05). Pro-LVH RAAS gene polymorphisms are associated with progressive septal hypertrophy and LVOT obstruction in children with HCM. Identification of RAAS modifier genes may help to risk-stratify patients with HCM. This work was presented in part at the Annual Scientific Sessions of the American Heart Association, New Orleans, November 2004.     

肥厚型心肌病患者认知功能障碍的发生及影响因素分析

目的:探讨肥厚型心肌病(HCM)患者认知功能障碍的发生及影响因素。方法:收集2018年4月至2019年7月期间空军军医大学第一附属医院超声医学科HCM患者198例。综合北京版蒙特利尔认知评估(MoCA)量表结果及教育程度,判断患者认知功能:文盲且MoCA得分14分、1年≤教育年限≤6年且MoCA得分20分、或教育年限6年且MoCA得分25分为认知功能障碍组(n=37),其余为认知功能正常组(n=161)。比较两组患者一般资料、超声心动图检查结果及认知功能评估结果。采用多因素logistic回归分析筛选HCM患者认知功能障碍的可能危险因素。结果:HCM患者认知功能障碍的发生率为18.7%(37/198)。与认知功能正常组相比,认知功能障碍组HCM患者年龄较大(P0.05),受教育年限较短(P0.05),心功能分级及左心室舒张功能较差(P0.05),激发左心室流出道压差较高(P0.05)。认知功能障碍组HCM患者MoCA得分较低(P0.05),尤其在视空间与执行功能和延迟回忆(P0.05)两项上得分较差。多因素logistic回归分析结果表明,调整年龄(OR=14.435, 95%CI:4.476-46.550; P0.001)和教育年限(OR=5.274, 95%CI:2.024-13.744; P=0.001)后,激发左心室流出道压差(OR=3.844, 95%CI:1.551-9.524; P=0.004)是HCM患者认知功能障碍的独立危险因素。结论:激发左心室流出道压差可以增加HCM患者认知功能障碍的发生风险。     

Two-dimensional tracking and TDI are consistent methods for evaluating myocardial longitudinal peak strain in left and right ventricle basal segments in athletes

Background

Surgical "anatomical" repair is the most frequent technique used to correct mitral regurgitation due to severe myxomatous valve disease. Debate, however, persists on the efficacy of this technique, as well as on the durability of the repaired valve, and on its functioning and hemodynamics under stress conditions. Thus, a basal and Dobutamine echocardiographic (DSE) study was carried out to evaluate these parameters at mid-term follow-up.

Methods and Results

Twenty patients selected for the study (12 men and 8 women, mean age 60 ± 9 years) underwent pre- and post-operative transthoracic echocardiography (TTE) and intra-operative transesophageal echocardiography (TEE). At mid-term follow-up (20 ± 5 months) all patients underwent rest TTE and DSE (3 min. dose increments up to 40 microg/Kg/min protocol). Pre-discharge and one-month TTE showed absence of MR in 11 pts., trivial or mild MR in 9 pts. and normal mitral valve area and gradients. Mid-term TTE showed decrease in left atrial and ventricular dimension, in pulmonary artery pressure (sPAP) and grade of MR. During DSE a significant increase in mitral valve area, maximum and mean gradients, sPAP, heart rate and cardiac output and a decrease in systolic annular diameter and left ventricular volume were found; in 6 pts. a transient left ventricular outflow tract obstruction was observed.

Conclusion

Basal and Dobutamine stress echocardiography proved to be valuable tools for evaluation of mid-term results of mitral valve repair. In our study population, the surgical technique employed had a favourable impact on several cardiac parameters, evaluated by these methods.