Effects of permanent dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy.

AIMS: To assess the effects of chronic dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy. METHODS AND RESULTS: Twenty-three patients with hypertrophic obstructive cardiomyopathy and mitral regurgitation. treated with DDD pacing for 16 +/- 14 months, were included in the study. Mitral regurgitation was assessed by Doppler-echocardiography using semi-quantitative analysis (grades I-IV) and by measuring the maximum regurgitant jet area/left atrial area ratio. At the end of follow-up, DDD pacing reduced the outflow gradient from 93 +/- 37 mmHg to 31 +/- 30 mmHg (P<0.0001). Nine of the 14 patients who initially had > or =grade II mitral regurgitation improved by at least one grade, two of them exhibiting dramatic improvement (from grade IV and III to grade I). The regurgitant jet area/left atrial area ratio was reduced with DDD pacing from 20 +/- 13% to 11 +/- 6% (P<0.0001). Patients who had significant mitral regurgitation despite pacing were those whose outflow gradient remained high or those with mitral valve organic abnormalities (mitral annulus calcification or mitral valve prolapse). In the absence of organic abnormalities other than leaflet elongation, there was a significant correlation between the gradient value achieved with DDD pacing and the extent of mitral regurgitation (P<0.05). CONCLUSION: In the absence of organic mitral valve abnormalities, DDD pacing reduces in parallel mitral regurgitation and left ventricular outflow gradient. In such patients therefore, significant mitral regurgitation is not a contraindication to pacing.     

Impact of dual-chamber permanent pacing in patients with obstructive hypertrophic cardiomyopathy with symptoms refractory to verapamil and beta-adrenergic blocker therapy.

BACKGROUND. Patients with obstructive hypertrophic cardiomyopathy (HCM) with symptoms refractory to drugs (beta-blockers or verapamil) are candidates for cardiac surgery (left ventricular septal myectomy or mitral valve replacement). The present study examines prospectively the ability of dual-chamber (DDD) pacing to improve symptoms and relieve left ventricular outflow obstruction in such patients. METHODS AND RESULTS. Forty-four consecutive patients with obstructive HCM who had failed to benefit from pharmacotherapy underwent treadmill exercise tests, echocardiography, and cardiac catheterization before and 1.5-3 months after implantation of a DDD pacemaker. Symptoms (angina, dyspnea, palpitations, presyncope, and syncope), New York Heart Association functional class status (1.7 +/- 0.7 versus 3.4 +/- 0.5, p less than 0.00001), and exercise durations were improved at follow-up evaluation. This was associated with significant reduction in left ventricular outflow tract gradient (38 +/- 38 versus 87 +/- 43 mm Hg, p less than 0.0001) and significant increases in cardiac output and systemic arterial pressures. Notably, when pacing was discontinued and comparisons were made in sinus rhythm, treadmill exercise durations were greater and left ventricular outflow tract gradients were less at the follow-up evaluation compared with the baseline study. CONCLUSIONS. DDD pacing is an effective alternative to surgery in most patients with obstructive HCM with drug-refractory symptoms. The beneficial effects of pacing continue to be evident when pacing is acutely discontinued.     

Long-term follow-up of patients with obstructive hypertrophic cardiomyopathy treated with dual-chamber pacing

In this study, patients with obstructive hypertrophic cardiomyopathy (HC) were treated with dual-chamber pacemaker therapy. Long-term follow-up analysis showed that dual-chamber pacemaker therapy in selected patients resulted in a significant reduction in symptoms and in the left ventricular outflow tract gradient, which was maintained up to 10 years after implantation. Dual-chamber pacing is of potential long-term benefit in selected groups of patients with obstructive HC.     

Effects of dual-chamber pacing on regional myocardial deformation in patients with hypertrophic obstructive cardiomyopathy.

BACKGROUND: This study examined the effects of dual-chamber pacing (DDD) on regional myocardial deformation, as determined by echocardiographic strain and strain rate (SR) imaging, in patients with hypertrophic obstructive cardiomyopathy (HOCM). METHODS AND RESULTS: Fourteen patients (11 men, 3 women; mean age 55 +/-16 years) who had been on long-term DDD (mean period 7.4 +/- 2.1 years) underwent strain and SR imaging. Before and after DDD, the peak strain (%) and SR (s(-1)) during systole were assessed in 8 segments in 4 left ventricular (LV) walls. With DDD turned on, peak strain and SR were significantly increased in the basal anteroseptal (strain -10.2 +/- 6.8 to -1.0 +/- 6.4, p<0.005; SR -0.76 +/- 0.46 to 0.05 +/- 0.58, p<0.001) and septal segments (strain -11.2 +/- 8.9 to -2.2 +/- 7.7, p<0.005; SR -0.85 +/- 0.54 to -0.19 +/- 0.75, p<0.05), but not in the basal posterior (strain -15.0 +/- 13.0 to -13.4 +/- 9.2, p=NS; SR -1.37 +/- 0.57 to -1.93 +/- 0.65, p=NS) and lateral segments (strain -18.1 +/- 10.2 to -15.7 +/- 5.6, p=NS; SR -1.33 +/- 0.68 to -0.84 +/- 0.88, p=NS). These findings were associated with a modest, but significant, change in the LV pressure gradient (24 +/- 12 mmHg to 14 +/- 7 mmHg, p<0.001). CONCLUSIONS: In patients with HOCM, DDD appeared to produce myocardial lengthening in the basal septum during systole, which may have implications for the mechanism of reducing LV outflow obstruction during DDD.     

Comparison of dual-chamber pacing with nonsurgical septal reduction effect in patients with hypertrophic obstructive cardiomyopathy

OBJECTIVES: The aim of the study was to compare the influence of dual-chamber pacing vs. nonsurgical septal reduction on hemodynamic and morphological parameters in patients with obstructive form of hypertrophic cardiomyopathy. METHODS: Nineteen patients with dual-chamber pacing (group I) and 9 patients who underwent nonsurgical septal reduction (group II) were studied at baseline and after a 6-month follow-up. The changes of left ventricular outflow tract gradient and posterior wall thickness (as an index of left ventricular hypertrophy regression) were compared. RESULTS: The baseline left ventricular outflow tract gradient was comparable between group I and group II (77+/-25 vs. 82+/-25 mm Hg, p>0.05). At 6-month follow-up, the left ventricular outflow tract gradient was reduced to a similar level in both groups (28+/-19 vs. 25+/-12 mm Hg, p>0.05). At baseline, posterior wall hypertrophy was comparable between groups (12.9+/-1.7 vs. 13.6+/-2.2 mm, p>0.05). During follow-up, the posterior wall thickness was unchanged in the pacing group (12.9+/-1.7 vs. 12.6+/-1.6 mm, p>0.05), whereas nonsurgical septal reduction induced regression of left ventricular hypertrophy in myocardial region remote from the infarcted septal segment (13.6+/-2.2 vs. 10.5+/-2.3 mm, p<0.003). CONCLUSION: Despite comparable reduction of instantaneous left ventricular outflow tract gradient, the nonsurgical septal reduction decreased posterior wall thickness, whereas pacing did not reduce left ventricular hypertrophy. Thus, regression of left ventricular hypertrophy that appeared solely after nonsurgical septal reduction may reflect the more permanent reduction of left ventricular pressure overload. Thus, not only hemodynamic but also morphological benefit from nonsurgical septal reduction seems to indicate the superiority of this method over dual-chamber pacing.     

Symptomatic hypertrophic obstructive cardiomyopathy: the role of dual-chamber pacing

BACKGROUND AND PURPOSE: The management of symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM) has traditionally consisted of beta blockers and calcium channel blockers. Surgical treatment has been employed for operable patients who became refractory to medical therapy. However, associated complications, mortality rate, and recurrence of functional limitations have shifted the focus toward alternative therapy modalities. Recently, permanent dual-chamber (DDD) pacemaker has been introduced as an alternative treatment option. PATIENTS AND METHODS: This study comprises clinical, angiographic, echocardiographic, and electrophysiologic data obtained at a single center on 10 symptomatic patients with HOCM who received a DDD pacemaker after medical therapy failed to relieve symptoms. Presenting symptoms were exertional dyspnea and chest pain (60%), syncope (20%), and presyncope (20%). These symptoms were documented for 8.9+/-7.1 years before pacemaker implantation. All patients were in New York Heart Association functional class III or IV before pacemaker therapy. RESULTS: Placement of a permanent DDD pacemaker decreased the left ventricular outflow tract gradient from 83+/-44 mm Hg (range: 35-180 mm Hg) to 47.1+/-25.3 mm Hg (range: 10-75 mm Hg) in these patients. Within 1 to 30 months, follow-up found that the functional status of eight out of the 10 patients had improved to New York Heart Association class 0 or I. CONCLUSION: In selected patients with symptomatic HOCM who fail to respond to medical therapy, DDD pacemaker may offer a nonsurgical alternative treatment option. Large-scale multicenter, prospective, randomized trials are needed to establish the role of this modality in the treatment of hypertrophic obstructive cardiomyopathy.     

Percutaneous transluminal septal myocardial ablation combined with permanent dual-chamber pacing in hypertrophic obstructive cardiomyopathy: a case report

A 74-year-old woman suffering from dyspnea on effort and chest pain (New York Heart Association functional class III) was admitted to our hospital. Echocardiography and left ventriculography showed severe hypertrophy of the left ventricular wall and a severe intraventricular pressure gradient of about 150 mmHg. The diagnosis was hypertrophic obstructive cardiomyopathy. The intraventricular pressure gradient was decreased from 157 to 68 mmHg by percutaneous transluminal septal myocardial ablation (PTSMA), but this reduction was not adequate. Thereafter, dual-chamber pacing was additionally performed. The intraventricular pressure gradient was decreased to 26 mmHg with no complication. PTSMA is a certain way to decrease pressure gradient, but has some complications. Permanent dual-chamber pacing also can show the same effect, but is inferior to PTSMA. Combination of these 2 methods succeeded in abolishing the intraventricular pressure gradient with no complication.     

Efficacy of alcohol septal ablation in mildly symptomatic or severely symptomatic patients with hypertrophic obstructive cardiomyopathy

<正>Objective To compare the prognosis of mildly or severely symptomatic patients with obstructive hypertrophic cardiomyopathy (OHCM) who underwentalcohol septal ablation (ASA).Methods This retrospective study cohort consisted of patients with OHCM who received ASA treatment in Beijing Anzhen Hospital,     

Evidence for anti-ischemic effect of dual-chamber pacing in patients with the obstructive form of hypertrophic cardiomyopathy

Dual-chamber pacing reportedly improves the quality of life by reducing the frequency of anginal episodes in selected patients with the obstructive form of hypertrophic cardiomyopathy (HCM), although the underlying mechanism or coronary effect is poorly understood. We report 3 patients with obstructive HCM, in whom the effects of atrial vs. dual-chamber tachypacing on systemic hemodynamics and myocardial lactate metabolism were studied. In all patients myocardial lactate production, objective evidence of myocardial ischemia, was demonstrated during atrial pacing, whereas no patient developed myocardial ischemia during dual-chamber pacing. By contrast, the responses of pressure gradient to pacing varied among the patients. These observations demonstrate for the first time that dual-chamber pacing exerted an anti-ischemic effect in obstructive HCM, which may contribute, at least partly, to the beneficial effects of chronic AV pacing on angina status and/or LV function.     

双腔起搏器治疗肥厚梗阻性心肌病的远期疗效评价

通过对 16例双腔起搏治疗的肥厚梗阻性心肌病(HOCM)患者长达 5年的血流动力学及超声心动图形态学随访观察 ,评价双腔起搏器治疗HOCM的远期疗效 ,长期起搏对心功能的影响及停止起搏后其血流动力学变化。资料和方法　经临床确诊HOCM患者行双腔起搏治疗 16例 ,其中男性 12例 ,女性 4例 ,平均年龄 4 5～ 6 8(5 6 4 4± 7 76 )岁 ,植入起搏器时间 5～ 8(5 89± 1 0 1)年 ,随访时间 5年。心功能(NYHA分级 )Ⅱ级 9例 ,Ⅲ级 6例 ,Ⅳ级 1例 ,均有不同程度晕厥、胸痛及呼吸困难。于植入DDD起搏器前 ,植入起搏器后 2年、5年 (AV间期为 12 0m…     

Transoesophageal left ventricular pacing in heart failure patients with permanent right ventricular pacing.

BACKGROUND: Previous studies of biventricular (BV) pacing for treatment of heart failure (HF) patients with left bundle branch block (LBBB) evaluated responders to BV pacing with acute transvenous left ventricular (LV) pacing and arterial pulse pressure (PP). The aim of this study was to assess transoesophageal LV pacing in evaluation of the haemodynamic response with a view to upgrading responders from permanent right ventricular (RV) pacing to BV pacing. METHODS AND RESULTS: Ten HF patients (age 62+/-8 years; one female, nine males) in NYHA III, LV ejection fraction 24+/-9% and permanent RV pacing by means of an implanted pacemaker or ICD were tested using transoesophageal LV pacing and PP. Permanently RV-paced HF patients were analysed with transoesophageal atrial sensed LV pacing in VAT mode with a different AV delay (n = 6) and with transoesophageal LV pacing in V00 mode during atrial fibrillation (n = 4). In five responders, PP was higher during transoesophageal LV pacing than PP during RV pacing (74+/-42 versus 57+/-31 mmHg, P = 0.015). Responders were upgraded by means of an LV lead via the coronary sinus in the posterior (n = 1) or posterolateral (n = 4) walls and after attaining a high LV pacing threshold with an epicardial LV lead on the anterior (n = 1) or anterolateral (n = 1) walls. NYHA class improved from 3 to 2+/-0.3 (P = 0.003) during 204+/-120 days follow-up and cardiac output increased from 4.4+/-1.5 to 5.6+/-1.7 l/min (P = 0.027) when comparing BV pacing and optimal AV delay with RV pacing. In five nonresponders, PP was not higher during transoesophageal LV pacing than during RV pacing. CONCLUSION: Transoesophageal LV pacing may be a useful technique to detect responders to BV pacing in permanently RV-paced HF patients.     

Effects of permanent dual chamber pacing on myocardial perfusion in symptomatic hypertrophic cardiomyopathy.

OBJECTIVES: To investigate whether disturbance of the cellular homoeostasis and integrity of cardiomyocytes in dilated cardiomyopathy (DCM) is accompanied by alterations in cell-matrix relations as indicated by changes in the deposition of fibronectin (FN) isoforms. DESIGN: Tissue from a case series of patients with DCM was investigated by immunohistochemistry with antibodies against FN (all variants, clone IST4), ED-A+ FN (clone IST9), ED-B+ FN (clone BC1), and oncofetal glycosylated FN (clone 5C10). The sites of de novo synthesis of FN were demonstrated by means of non-radioactive RNA in situ hybridisation (ISH) with biotinylated FN cDNA fragments as the probe. SETTING: University hospital. PATIENTS: Samples from 10 patients with clinical criteria and histological diagnosis of DCM and from 3 individuals with normal hearts. INTERVENTIONS: Samples were obtained by right ventricular endomyocardial biopsy. MAIN OUTCOME MEASURE: Distribution of oncofetal FN variants in DCM hearts. RESULTS: Immunostaining of FN (IST4, all variants) showed a coarse interstitial network in normal and diseased myocardium. ED-A+ FN was deposited as fine interstitial spots in normal myocardium and in DCM samples. Immunostaining for oncofetal glycosylated FN and ED-B+ FN was not seen in normal adult myocardium, whereas myocardium from DCM patients showed focal and delicate staining in the interstitium. RNA ISH showed that these deposits resulted from local FN synthesis. CONCLUSION: The results accord with de novo expression of oncofetal FN variants in hearts from patients with DCM. The oncofetal FN variants may serve as disease markers in myocardium affected by DCM.     

双心腔起搏治疗肥厚梗阻性心肌病患者的长期随访

目的　评价双心腔起搏对肥厚梗阻性心肌病患者的远期疗效。方法　 15例确诊为肥厚梗阻性心肌病并植入双心腔起搏器的患者 ,男性 11例 ,女性 4例 ,平均年龄 (5 0 2± 15 5 )岁 ,程控为DDD起搏方式。对患者术前、术后第 1次随访平均 (5 1± 1 6 )个月及最近 1次随访平均(2 7 3± 3 7)个月的临床症状、心功能、和超声心动图下的血流动力学指标进行分析。结果　 9例晕厥患者在第 1次评价时即未再发作 ,2例先兆晕厥的患者 ,在第 1次评价时仍有 1例有偶发 ,但在第2次评价时症状也消失。 15例气促、 13例胸痛、 12例心悸患者 ,在第 1次评价时分别有 6例、 7例、6例症状完全消失 ,总消除率约 4 0 %。在第 2次评价时又分别有 5例、 2例、 3例患者症状完全消失 ,进一步症状消除率约 2 0 %。患者左心室流出道跨瓣压差由术前平均 (79 9± 32 6 )mmHg (1mmHg=0 133kPa) ,经半年起搏治疗后降为 (43 2± 18 9)mmHg ,3年后进一步降为 (40 4± 2 4 1)mmHg ,两次结果与术前比较均有统计学意义 (P <0 0 1) ;心功能由术前的 (2 6± 0 4 )级 (NYHA分级 ) ,提高到第 1次随访时的 (1 7± 0 3)级 (P <0 0 1) ,第 2次随访时的 (1 1± 0 2 )级 (P <0 0 1) ;E/A峰值 ,在术前、第 1次随访、第 2次随访时分别为 0 8±     

起搏治疗肥厚梗阻型心肌病的长期疗效观察

摘要 目的 评价起搏治疗对肥厚梗阻型心肌病(hypertrophic obstructive cardiomyopathy，HOCM)左室流出道梗阻及临床症状的长期疗效。方法 25例HOMC患者接受起搏治疗，临床随访12个月，观察临床症状体征；采用超声心动图观察起搏前后室间隔厚度(IVS)、左室后壁(LVPW)、左室舒张末内径（LVDd）、左室收缩末内径（LVDs）、左房内径（LAD）、跨左室流出道压力阶差（LVOT）、及二尖瓣前向运动程度（SAM）、二尖瓣反流的变化。结果 25例患者中植入双腔生理性起搏器21例，占84%，单腔SSIR起搏4例，占16%。起搏治疗12个月后，临床症状明显改善，15例晕厥发作术后症状完全消失，劳力性呼吸困难、胸痛改善分别占82.6%和75.0%， LVOT显著下降，从术前89.7±23.8 mmHg 降至术后36.8±12.6 mmHg ，P<0.01，IVS、LAD、MVA减少，SAM运动明显改善，其他指标无显著变化。结论起搏治疗对HOCM长期临床效果满意。     

肥厚梗阻性心肌病双腔起搏与经皮室间隔化学消融治疗的远期疗效分析

目的 回顾性分析肥厚梗阻性心肌病患者行双腔起搏器植入(PM)或经皮室间隔化学消融(PTMSA)治疗,评价两种治疗方法的远期疗效.方法 48例患者,19例行PM治疗,29例行PTMSA治疗,并随访超声心动图结果.电话随访患者的临床症状.结果 PM组,平均年龄(51±13)岁,平均随访时间(3.9±2.3)年,起搏模式为DDD,AV延迟间期90～110 ms,治疗前后左心室流出道压力阶差分别是(103.8±40.6)mm Hg(1 mm Hg=0.133 kPa)和(45.1±36.2)mm Hg,P<0.05.PTMSA组,平均年龄(43±11)岁,随访时间(3.6±1.2)年,治疗前后左心室流出道压力阶差分别是(85.7±21.1)mm Hg和(24.6±12.2)mm Hg,P<0.05.PTMSA组左心室流出道压力阶差下降幅度大于PM治疗组[(71±12)%vs(58±29)%,P<0.05].PTMSA术后并发症为心律失常,发生率38%,主要为各种心律失常;PM术后主要为起搏器相关并发症发生率5.3%,主要为起搏器相关并发症.PTMSA组14例有晕厥史的患者中有1例术后活动时仍偶发晕厥,胸痛、胸闷症状缓解率75%.PM组10例有晕厥史的患者术后未再发,胸痛、胸闷症状缓解率93.8%.结论 双腔起搏器及经皮室间隔化学消融治疗肥厚梗阻性心肌病均可降低患者的左心窒流出道压力阶差,起搏治疗降低危心室流出道雎力阶差的幅度低于消融治疗.消融治疗的并发症高于起搏治疗.两种治疗方法均可改善患者临床症状.     

老年肥厚型梗阻性心肌病消融和起搏器治疗的对照观察

目的比较老年肥厚型梗阻性心肌病患者接受经冠状动脉消融肥厚心肌（TASH）或起搏器治疗的有效性和安全性。方法23例充分药物治疗不满意,心功能Ⅲ级（NYHA）以上的老年肥厚型梗阻性心肌病患者随机接受心肌声学造影指导下的TASH或根据血压优化PR间期的右心双腔起搏器治疗。其中2例接受TASH治疗者并发永久起搏器依赖而安装永久起搏器。对单纯接受TASH（13例）或起搏器（8例）治疗者进行了平均24个月的随访。结果接受两种治疗方法的患者心功能和主观症状积分均得到显著的改善。TASH组心功能由3．2±0．7级改善到1．5±0．5级,综合症状积分由5．9±1．6下降到1．8±0．7,P均〈0．001。起搏器治疗组心功能也由3．0±0．1改善到1．9±0．6级,综合症状积分也由4．5±1．3下降到2．3±1．6,P均〈0．01。综合症状改善程度TASH组明显优于起搏器治疗（4．2±1．5比2．3±1．3,P=0．007）。左心室流出道压力阶差TASH组平均下降了（79．9±35．5）mmHg（1mmHg=0．133kPa,P〈0．001）,起搏器治疗组平均下降了（49．3±37．7）mmHg（P〈0．05）,平均下降率分别为84％和53％。左心室流出道压力阶差下降率〉75％和〈50％TASH组分别有10例和1例,起搏器治疗组分别有4例和3例。TASH组治疗后室间隔厚度、左室舒张末径、收缩末径与术前比较变化显著[分别为（22．2±4．1）mm比（17．1±3．2）mm,（41．5±5．3）mm比（44．7±4．6）mm,（23．5±4．4）mm比（28．3±3．6）mm,P均〈0．05],但没有左室收缩功能异常。随访中,TASH组3例阵发性心房颤动中有2例转为慢性心房颤动,起搏器治疗组中2例阵发性心房颤动中1例发展成慢性心房颤动。结论TASH和起搏器治疗两种方法均能使老年肥厚型梗阻性心肌病患者心功能和综合症状得到显著改善,综合症状改善TASH优于起搏器治疗。TASH显著降低左心室流出道压力阶差,起搏器治疗中等程度降低心室流出道压力阶差。TASH导致的左心室流出道重构不会导致老年肥厚型梗阻性心肌病患者收缩功能的异常和左心室的扩张,但同样存在并发症,甚至严重并发症发生的可能。