Serial electrocardiographic and angiographic changes of patients with hypertrophic cardiomyopathy

The characteristics of ECG findings as they relate to myocardial changes during long-term course of hypertrophic cardiomyopathy (HCM) were studied. Serial changes in ECG were compared with changes left ventriculogram and bi-ventriculogram in 15 patients with HCM without intraventricular conduction disturbance. Serial changes in ECG findings, with special reference to the negative T wave, were categorized in three groups; 1) 5 patients with increase or appearance of the negative T wave (A-1 group). 2) 4 patients with decrease or disappearance of the negative T wave (A-2 group). 3) 6 patients without significant changes in the T wave (B-group). A-1 group presented a marked increase in SV1 + RV5, and of the thickness of anterior and apical wall, and a decrease of the peak dV/dt/EDV (end diastolic volume-normalized peak filling rate), serially. End diastolic volume (EDV) and ejection fraction (EF) did not change significantly. The configuration of left ventriculogram changed from a round form to a spade-like form. A-2 group presented a marked decrease in SV1 + RV5, the thickness of anterior and apical wall, peak dV/dt/EDV and peak dV/dt/V (left ventricular volume of the time of peak filling-normalized peak filling rote). EF decreased serially, 2 cases of A-2 group presented the clinical picture of dilated cardiomyopathy in the end stage. In B group, SV1 + RV5, the wall thickness and left ventricular function did not change, serially. In conclusion, serial observations of ECG are useful for assessing alterations in wall thickness, LV-form and LV-function.     

Electrocardiographic and angiographic follow-up of patients with hypertrophic cardiomyopathy

Electrocardiographic follow-up was conducted for 17 patients with hypertrophic cardiomyopathy including six cases who received left ventriculographic follow-up. 1. Serial ECG changes were as follows: 1) In seven patients negativity of the T wave appeared or increased concomitantly with increased voltage of SV1 + RV5 (A-1 group). 2) In four patients, negativity of the T wave decreased or disappeared with the decreased voltage of SV1 + RV5 (A-2 group). 3) In six patients, there were insignificant changes of both T wave and SV1 + RV5 (B group). 2. Results of serial left ventriculography and biventriculography were as follows: 1) Two patients (A-1 group) showed an increased voltage of SV1 + RV5 (25 mm----48 mm, 42 mm----54 mm), and increased thickness of the apical wall (10 mm----12 mm, 8 mm----11 mm) and the anterior wall (13 mm----16 mm, 10 mm----16 mm). However, the thickness of the posterior and interventricular septal walls did not change. The configuration of the end-diastolic left ventriculogram (RAO 30 degrees) changed from a round configuration to the so-called "beak" configuration. 2) Two patients (A-2 group) showed a decreased voltage of SV1 + RV5 (81 mm----26 mm, 73 mm----53 mm), decreased thickness of the apical wall (18 mm----10 mm, 21 mm----15 mm) and the anterior wall (12 mm----9 mm, 17 mm----12 mm). The end-diastolic left ventriculogram changed from a spade-like configuration to a round configuration. In the analysis of diastolic function measured by digitized cineangiograms using a picture-analyzer, diastolic dysfunction was already present at the initial observation. The diastolic and systolic dysfunction progressed during serial observations. These patients showed the clinical pictures of dilated cardiomyopathy at the final observation. 3) Two patients with no remarkable changes of the T wave (B group) showed insignificant changes in configuration of the left ventriculogram and wall thickness. In conclusion, serial changes in configuration of the left ventricle and wall thickness, especially of the anterior and apical walls, are compatible with the serial changes of the ECG in hypertrophic cardiomyopathy. The patients whose negative T waves decreased or disappeared had diastolic dysfunction at the initial observation, and deterioration of both diastolic and systolic dysfunctions during serial observations.     

Regression of giant negative T waves in hypertrophic cardiomyopathy: cases simulating either dilated cardiomyopathy or severe coronary artery stenosis

Two cases of hypertrophic cardiomyopathy (HCM), in whom giant negative T waves resolved during 10 years, are reported. Case 1: A 33-year-old man was admitted in 1975 for careful evaluation because of an ECG abnormality. The ECG revealed a giant negative T wave (GNT) in V5 (-15 mm) and high voltage (SV1 + RV5 = 81 mm). The thickness of the apical wall was 18 mm; the anterior wall, 12 mm; the posterior wall, 16 mm; and the interventricular septum, 17 mm on the left ventriculogram and biventriculogram. The coronary angiogram was normal. From these data, this patient was diagnosed as having HCM. However, follow-up studies disclosed resolution of the GNT with decreased high voltage (SV1 + RV5 = 26 mm). The catheterization performed in 1985 showed a decrease of wall thickness: the apical wall to 10 mm; the anterior wall, 9 mm; the posterior wall, 14 mm; and the interventricular septum, 14 mm. Ejection fraction was markedly decreased from 79.8% to 27.1%, and the wall motion was generally reduced. The coronary angiogram was normal. These findings resemble the clinical pictures of dilated cardiomyopathy (DCM). Case 2: A 58-year-old man was admitted in 1974 because of easy fatiguability. His ECG revealed a GNT in V4 (-10 mm) and high voltage (SV1 + RV5 = 75 mm). The patient was diagnosed as having HCM by cardiac catheterization, right ventricular biopsy and other procedures. In 1985, the depth of the GNT and the voltage of SV1 + RV5 regressed significantly (SV1 + RV5 = 26 mm). The thickness of the apical wall was, 12 mm; the anterior wall, 19 mm; the posterior wall, 13 mm; and the interventricular septum 14 mm during recatheterization. Coronary angiography disclosed stenoses of the left main trunk (75%), the left anterior descending artery (99%) and the left circumflex artery (50%). The right coronary artery was totally occluded. In conclusion, these two cases of HCM had similar changes in their ECG during long-term follow-up studies, but the process was different. One case finally showed clinical pictures of DCM; the other, severe coronary stenoses. These suggested that blood flow to the myocardium is an important determinant for the development of clinical features simulating DCM in cases with HCM.     

Types of left ventricular hypertrophy and their functional changes in essential hypertension

104 patients of hypertensive left ventricular hypertrophy (LVH) were studied by two-dimensional echocardiography. According to the changes of left ventricular wall thickness, wall mass, end-diastolic volume and ejection fraction, they were divided into three types (concentric, dilated, disproportionate): (1) Concentric LVH 83 cases (79.8%) with thickened ventricular wall and augmented mass. (2) Dilated LVH 13 cases (12.5%) with left ventricular cavity enlarged and both ventricular mass and volume increased, ejection fraction decreased. (3) Disproportionate LVH 8 cases (7.7%), similar to hypertrophic cardiomyopathy with excess increase in interventricular septal thickness. The thickness ratio between interventricular septal and left ventricular posterior wall was greater than or equal to 1.3.     

Evaluation of the electrocardiogram RV5/V6 criteria in the diagnosis of left ventricular hypertrophy in marathon runners

To assess the value of electrocardiogram (ECG) RV5/V6 criteria for diagnosing left ventricular hypertrophy (LVH) in marathons. A total of 112 marathon runners who met the requirements for “Class A1” events certified by the Chinese Athletics Association in Changzhou City were selected, and their general clinical information was collected. ECG examinations were performed using a Fukuda FX7402 Cardimax Comprehensive Electrocardiograph Automatic Analyser, whereas routine cardiac ultrasound examinations were performed using a Philips EPIQ 7C echocardiography system. Real-time 3-dimensional echocardiography (RT-3DE) was performed to acquire 3-dimensional images of the left ventricle and to calculate the left ventricular mass index (LVMI). According to the LVMI criteria of the American Society of Echocardiography for the diagnosis of LVH, the participants were divided into an LVMI normal group (n = 96) and an LVH group (n = 16). The correlation between the ECG RV5/V6 criteria and LVH in marathon runners was analysed using multiple linear regression stratified by sex and compared with the Cornell (SV3 + RaVL), modified Cornell (SD + RaVL), Sokolow–Lyon (SV1 + RV5/V6), Peguero–Lo Presti (SD + SV4), SV1, SV3, SV4, and SD criteria. In marathon runners, the ECG parameters SV3 + RaVL, SD + RaVL, SV1 + RV5/V6, SD + SV4, SV3, SD, and RV5/V6 were able to identify LVH (all p < .05). When stratified by sex, linear regression analysis revealed that a significantly higher number of ECG RV5/V6 criteria were evident in the LVH group than in the LVMI normal group (p < .05), both with no adjustment and after initial adjustment (including age and body mass index), as well as after full adjustment (including age, body mass index, interventricular septal thickness, left ventricular end-diastolic diameter, left ventricular posterior wall thickness, and history of hypertension). Additionally, curve fitting showed that the ECG RV5/V6 values increased with increasing LVMI in marathon runners, exhibiting a nearly linear positive correlation. In conclusions, the ECG RV5/V6 criteria were correlated with LVH in marathon runners.     

Electrocardiographic and echocardiographic changes after one to two-years' treatment of hypertension. Analyses of voltages (Sv1+RV5), wall thickness, cavity, mass, and hemodynamics of the left ventricle

The changes of left ventricular anatomy and function following treatment with antihypertensive agents for 1 to 2 years were studied by echo-cardiography in 34 patients with hypertension whose blood pressures and electrocardiographic voltages (SV1+RV5) were significantly decreased (p less than 0.001 and 0.01, respectively). The drugs administered or used were trichlormethiazide, beta-blockers, alpha-methyldopa, clonidine hydrochloride, and guanethidine. Most patients received 2 or more of the above drugs. The interventricular septal thickness, the left ventricular posterior wall thickness, the calculated left ventricular mass, the atrial dimensions, all decreased following treatment of hypertension for 1 to 2 years (p less than 0.001-0.05), and the ejection fraction improved (p less than 0.001). It is concluded that cardiac hypertrophy is not irreversible in patients with hypertension if their blood pressure is adequately controlled.     

Comparison of usefulness of Sokolow and Cornell criteria for left ventricular hypertrophy in subjects aged <20 years versus >30 years

The use of electrocardiography in sports or military screening is considered an effective tool for diagnosing potentially fatal conditions. The present study was designed to compare the yield of electrocardiographic criteria for left ventricular hypertrophy (LVH) criteria for the diagnosis of LVH and hypertrophic obstructive cardiomyopathy in subjects aged <20 years and >30 years. The association between the electrocardiographic (ECG) criteria for LVH (ECG-LVH) and echocardiographic findings was compared in 4 groups of air force academy candidates: (1) young candidates undergoing echocardiography because of ECG-LVH findings (n = 666); (2) young candidates without ECG-LVH findings undergoing routine echocardiography (n = 4,043); (3) older designated aviators undergoing echocardiography because of ECG-LVH findings (n = 196); and (4) older designated aviators undergoing routine echocardiography without ECG-LVH findings (n = 1,098). The predictive value of ECG-LVH findings for echocardiographic LVH, left ventricular mass, posterior wall thickness, and interventricular septal thickness were compared among the 4 groups. The ECG criteria in young subjects correlated with the left ventricular mass and posterior wall thickness but not with the interventricular septal thickness. In older subjects, these criteria correlated with left ventricular mass, interventricular septal, and posterior wall thickness. The positive and negative predictive value of ECG-LVH findings for the echocardiographic diagnosis of LVH in young subjects was 6.0% and 99.0%, respectively. In older subjects the positive and negative predictive value of ECG-LVH findings was 34% and 93%, respectively. In conclusion, ECG criteria are probably a useful tool for exclusion of LVH in young and older subjects; however, their low positive predictive value would probably lead to unnecessary echocardiographic tests, particularly in young subjects.     

肥厚性心肌病患者右心室结构与功能变化的分析

目的:应用彩色多普勒组织成像(CDTI)技术探讨肥厚性心肌病(HCM)患者右心室结构与功能的变化。方法:HCM患者35例(HCM组),正常对照组30例,应用CDTI测量左、右心室腔大小,室壁厚度,心室流出道等指标,于心尖四腔切面记录舒张期血流频谱,测量右室等容舒张时间(IRT)、等容收缩时间(ICT)、右室射血时间(RVET)及Tei指数。结果:与正常对照组比较,HCM患者右室前壁厚度[(4.56±0.70)mm比(5.43±0.87)mm]、室间隔厚度[(8.66±2.51)mm比(20.53±3.37)mm]、左室后壁厚度[(9.10±2.24)mm比(13.06±1.68)mm]均明显增加(P<0.05或<0.01),右室Tei指数[(0.39±0.61)比(0.80±0.38)]显著升高(P<0.01),右室流出道、右室舒张末期内径两组间无显著差异(P>0.05)。结论:肥厚性心肌病患者中右心室解剖结构与功能均受影响;右室Tei指数可以反映右心收缩及舒张功能变化。     

心电图诊断老年男性左心室肥厚的价值

目的 探讨心电图诊断老年男性左心室肥厚的价值.方法 回顾性分析我院自1990年进行尸体解剖的老年男性患者资料,排除心电图QRS波时限≥10.12 s及起搏心电图的患者,测量死亡前3个月内标准12导联心电图QRS波振幅,分析老年男性不同年龄组心电图QRS波振幅与左心室前壁厚度的相关性.结果 心电图V5、V6、I、aVL导联R波幅度[分别为(1.1±0.7)mV、(0.9±0.6)mV、(0.4±0.3)mV和(0.3±0.3)mV]及心电图左胸导联(V5或V6)R波幅度与右胸导联(V1)S波幅度之和[(1.9±1.2)mV)与左心室前壁厚度[(13.6±5.4)mm]具有相关性(相关系数分别为0.22、0.14、0.22、0.23、0.23;P均<0.05).心电图左胸导联(V5或V6)R波幅度与右胸导联(V1)S波幅度之和与左心室前壁厚度的相关性60～79岁组最强(相关系数为0.48,P<0.01),80～89岁组二者相关性减弱(相关系数为0.23,P<0.05),而90～101岁组二者无相关性(相关系数为0.03,P>0.05).结论 心电图左心室肥厚诊断标准在90岁以下老年男性中具有可靠性.     

Eelectrocardiographic correlates of ultrasonically increased septal, left ventricular posterior wall and left ventricular internal dimensions.

The electrocardiograms (ECG) of 64 subjects who exhibited an echocardiographically demonstrable increase in thickness of the interventricular septum and left ventricular posterior wall (Group 1, 22 patients), isolated left ventricular internal dimension (Group 2,26 patients), combined wall thickness and chamber diameter (Group 3, 2 patients), and septal thickness, (Group 4, asymmetric septal hypertrophy, 14 patients) were reviewed in order to determine sensitivity of ECG criteria for the diagnosis of left ventricular hypertrophy (LVH) proposed in 1949 by Sokolow and Lyon (13), in 1968 by Romhilt and Estes (14), and in 1973 the New York Heart Association (15). Relative sensitivity of the three methods was as follows: Total group, NYHA (77%) greater than Sokolow and Lyon (67%) greater than Romhilt and Estes (58%); Group 1, NYHA (91%) greater than Sokolow and Lyon (73%) greater than Romhilt and Estes (54%); Group 2, NYHA and Sokolow and Lyon (65%) greater than Romhilt and Estes (61%); Group 4, NYHA (79%) greater than Sokolow and Lyon (64%) greater than Romhilt and Estes (57%). We conclude that 1)ECG criteria of the NYHA for the diagnosis of LVH correlate best with an increase of ultrasonically determined septal, left ventricular posterior wall or left ventricular internal dimensions when compared with voltage criteria of Sokolow and Lyon and the point score system of Romhilt and Estes; and 2) isolated increase of left ventricular internal dimension, in the absence of thickened septum or posterior left ventricular wall, frequently results in ECG criteria compatible with the diagnosis of LVH.     

Electrocardiographic correlates of ultrasonically increased septal,left ventricular posterior wall and left ventricular internal dimensions

The electrocardiograms (ECG) of 64 subjects who exhibited an echocardiographically demonstrable increase in thickness of the interventricular septum and left ventricular posterior wall (Group 1,22 patients), isolated left ventricular internal dimension (Group 2, 26 patients), combined wall thickness and chamber diameter (Group 3, 2 patients), and septal thickness, (Group 4, asymmetric septal hypertrophy, 14 patients) were reviewed in order to determine sensitivity of ECG criteria for the diagnosis of left ventricular hypertrophy (LVH) proposed in 1949 by Sokolow and Lyon (13), in 1968 by Romhilt and Estes (14), and in 1973 the New York Heart Association (15). Relative sensitivity of the three methods was as follows: Total group, NYHA (77%) > Sokolow and Lyon (67%) > Romhilt and Estes (58%); Group 1, NYHA (91%) > Sokolow and Lyon (73%) > Romhilt and Estes (54%); Group 2, NYHA and Sokolow and Lyon (65%) > Romhilt and Estes (61%); Group 4, NYHA (79%) > Sokolow and Lyon (64%) > Romhilt and Estes (57%). We conclude that (1) ECG criteria of the NYHA for the diagnosis of LVH correlate best with an increase of ultrasonically determined septal, left ventricular posterior wall or left ventricular internal dimensions when compared with voltage criteria of Sokolow and Lyon and the point score system of Romhilt and Estes; and (2) isolated increase of left ventricular internal dimension, in the absence of thickened septum or posterior left ventricular wall, frequently results in ECG criteria compatible with the diagnosis of LVH.     

Spontaneous cardiac resynchronization

A 73-year-old woman with dilated cardiomyopathy presented with heart failure. The ECG showed sinus rhythm with left bundle branch block, left-axis deviation and prolonged QRS duration and frequent ventricular premature complexes from the left ventricular septal wall were present. Ventricular premature beats had narrower QRS duration than sinus node beats conducted through the His-purkinje fibers consistent with resynchronizing beats. The mechanisms of narrowing of the QRS complex produced by premature beats in cases of impaired intra and interventricular conduction are discussed.     

肥厚型心肌病的超声心动图及心电图分析

目的观察肥厚型心肌病的心电图和超声心动图特点。方法对临床确诊的32例肥厚型心肌病患者心电图、超声心动图资料进行回顾性分析。结果所有患者心电图均有异常,以ST-T改变、左室高电压和异常Q波为多见。Q波深度与室间隔厚度、ST压低深度与心尖部室壁厚度均呈正相关,而T波深度与心尖部室壁厚度无相关性,但与心尖部和室间隔的室壁厚度差呈正相关,左房大小与平均室壁厚度呈正相关。结论在肥厚型心肌病中,心电图和超声心动图中的许多异常指标具有相关性,两者结合可提高本病诊断率。     

肥厚型梗阻性心肌病经酒精室间隔消融术后心脏结构及功能变化

目的 探讨经皮穿刺腔内酒精室间隔心肌消融术（percutaneous transluminal alcohol septal myocardial ablation,PTSMA）对肥厚型梗阻性心肌病（hypertrophic obstructive cardiomyopathy,HOCM）患者心脏结构及功能的影响.方法 收集2006年1月至2012年12月在成都市第三人民医院住院的HOCM患者24例,比较其PTSMA术前、术后3个月及术后12个月的左心室流出道压力阶差、室间隔厚度、左心室后壁厚度、左心房内径、左心室舒张末期内径、纽约心脏病协会（NYHA）心功能分级、左心室射血分数和左心室短轴缩短率的变化.结果 HOCM患者进行PTSMA术后3个月及术后12个月左心室流出道压力阶差、室间隔厚度、左心室后壁厚度、左心房内径、左心室舒张末期内径、纽约心脏病协会心功能分级、左心室射血分数和左心室短轴缩短率与术前比较,差异有统计学意义（P＜0.05）;术后12个月相比术后3个月,以上指标变化差异无统计学意义（P＞0.05）.结论 PTSMA能显著改善HOCM患者左心室流出道梗阻及降低室壁厚度,改善患者心功能,是有效的治疗方法.     

Q waves in hypertrophic cardiomyopathy in relation to the distribution and severity of right and left ventricular hypertrophy

The cause of abnormal Q waves in hypertrophic cardiomyopathy remains unclear. Myocardial wall thickness was assessed by two-dimensional echocardiography at 8 left ventricular and 10 right ventricular sites in 67 patients (mean age 40 years) with hypertrophic cardiomyopathy and the findings were analyzed in relation to the presence of abnormal Q waves on the 12 lead rest electrocardiogram (ECG). Nineteen (28%) of the 67 patients had abnormal Q waves. Right ventricular hypertrophy was significantly more common in patients without abnormal Q waves (25 [52%] of 48 versus 2 [11%] of 19, p less than 0.001). With univariate analysis, there were six measurements that were significantly associated with abnormal Q waves: an increase in upper anterior septal thickness (p less than 0.005) and maximal left ventricular wall thickness (p less than 0.02), a decrease in mean and maximal right ventricular wall thickness (both p less than 0.005) and an increase in the ratio of both upper anterior septal to mean right ventricular wall thickness (p less than 0.005) and upper anterior septal to upper posterior wall thickness (p less than 0.005). With multivariate analysis, only the ratios of upper anterior septal to mean right ventricular wall thickness (p less than 0.005) and to upper posterior wall thickness (p less than 0.05) were significantly related to the presence of abnormal Q waves and predicted Q wave location with a sensitivity, specificity and predictive accuracy of 90%, 88% and 89%, respectively. In hypertrophic cardiomyopathy, the presence of abnormal Q waves on the 12 lead ECG is primarily a function of the relation of right ventricular wall thickness and upper anterior septal thickness.     

时间-空间相关成像技术对糖尿病患者妊娠期胎儿心脏结构及心室收缩功能的评估

目的:利用时间-空间相关成像(STIC)技术观察妊娠期糖尿病对胎儿心脏结构及心室收缩功能的影响。方法:妊娠期糖尿病孕妇96例,其中饮食控制组71例,胰岛素治疗组25例,同期相应孕周的正常妊娠孕妇176例作为对照组。运用STIC技术后处理软件获得M型图像测量心室侧壁及室间隔厚度;运用STIC技术后处理软件获得容积数据,测量胎儿左、右心室收缩末期(EDV)、舒张末期容积(ESV),计算左、右心室每搏输出量(SV)、心输出量(CO)及射血分数(EF);比较妊娠期糖尿病胎儿胰岛素治疗组、饮食控制组与正常对照组的心脏结构及心室收缩功能的变化。结果:妊娠28周以前,胎儿心脏的各项测量指标在胰岛素治疗组、饮食控制组及正常对照组间差异均无统计学意义(P>0.05);妊娠28周以后,胰岛素治疗组胎儿心室侧壁及室间隔厚度均大于正常对照组胎儿,差异有统计学意义(P<0.05);妊娠28周以后,妊娠期糖尿病胎儿胰岛素治疗组、饮食控制组与正常对照组左、右心室收缩功能三组间差异无统计学意义(P>0.05)。结论:妊娠期糖尿病对胎儿心脏结构的影响主要在孕晚期。妊娠28周以后,妊娠期糖尿病胰岛素治疗组胎儿较正常妊娠胎儿心室侧壁及室间隔均有增厚;但胎儿左、右心室收缩功能无明显变化。     

Echocardiographic characterization of the reversible cardiomyopathy of hypothyroidism

Nineteen patients with untreated hypothyroidism were evaluated by M-mode echocardiography. Asymmetric septal hypertrophy (ASH), defined as a ratio of interventricular septal thickness to left ventricular posterior wall thickness (IVS/LVPW) equal to or greater than 1.3, was identified in 17 cases. Additional abnormalities recognized by echocardiography included reduced amplitude of systolic septal excursion (SSex) [13 patients], reduced per cent of systolic septal thickening (%SST)[19 patients], reduced left ventricular outflow tract dimension (LVOT)[five patients] and systolic anterior motion of the mitral valve (SAM)[five patients]. These findings are similar to some of the echocardiographic features of idiopathic hypertrophic subaortic stenosis (IHSS). In 10 patients who returned to euthyroid state with L-thyroxine therapy, these abnormalities resolved. We conclude that long-standing hypothyroidism leads to a reversible cardiomyopathy, manifested by asymmetric septal hypertrophy with or without other echocardiographic features of a hypertrophic obstructive cardiomyopathy. This previously unrecognized features of hypothyroidism has important diagnostic and therapeutic implications.     

Left ventricular structural adaptations to obstructive sleep apnea in dilated cardiomyopathy

RATIONALE AND OBJECTIVES: Obstructive sleep apnea is common among patients with heart failure and exposes the left ventricle to trophic mechanical and adrenergic stimuli. We hypothesized that in heart failure patients with nonischemic dilated cardiomyopathy (a condition characterized by eccentric hypertrophy), those with obstructive sleep apnea would have a higher prevalence of left ventricular hypertrophy by wall thickness criteria (> or = 12 mm), and greater septal thickness than those without obstructive sleep apnea. METHODS AND RESULTS: We performed echocardiography and polysomnography in 47 patients with nonischemic dilated cardiomyopathy. Obstructive sleep apnea was present in 45% of these patients. The prevalence of left ventricular hypertrophy was greater in those with than in those without obstructive sleep apnea (47.6 vs. 15.4%, p = 0.016). Interventricular septal thickness (p < 0.001) and relative wall thickness (p = 0.011) were significantly greater in those with than in those without obstructive sleep apnea. However, there was no significant difference in posterior wall thickness between the groups. The frequency of obstructive apneas and hypopneas during sleep was the only significant independent correlate of septal thickness (p = 0.001). CONCLUSIONS: In patients with nonischemic dilated cardiomyopathy, the presence of obstructive sleep apnea is associated with an increased prevalence of left ventricular hypertrophy. The higher relative wall thickness and interventricular septal thickness in patients with obstructive sleep apnea indicate that the left ventricle is relatively less eccentric than in patients without obstructive sleep apnea, and that such remodeling affects mainly the septum. These structural adaptations may reflect unique nocturnal mechanical and adrenergic stimuli associated with obstructive sleep apnea.     

经胸超声心动图评价高血压心脏病与左心室流出道梗阻的应用价值

目的:应用经胸超声心动图(transthoracic echocardiography,TTE),评价高血压心脏病与肥厚型心肌病(HCM)左心室流出道梗阻的二维及血流动力学特征,为临床鉴别诊断提供影像学依据。方法:左心室流出道梗阻患者31例,其中高血压性左心室流出道梗阻12例,肥厚型梗阻性心肌病19例,二维图像下测量两组患者的室间隔厚度及左心室后壁厚度,在静息状态和激发试验后测量两组患者的左心室流出道流速及最大压差,分别进行组间及组内比较。结果:室间隔厚度肥厚型心肌病组(19.6±1.8)mm明显高于高血压组(12.4±0.6)mm,差异有统计学意义(P<0.05)。左心室后壁厚度:肥厚型心肌病组(11.5±0.5)mm,高血压组(11.3±0.6)mm,两组间比较差异无统计学意义(P>0.05)。高血压组组内比较激发试验后左心室流出道流速(398.6±36.7)cm/s及压差[(68.4±12.9)mmHg,1 mmHg=0.133kPa],均高于静息状态下流速178.2±23.4)cm/s,压差(13.5±6.2)mmHg,差异有统计学意义(P<0.05)。结论:经胸超声心动图能准确评价左心室流出道梗阻的解剖结构与血流动力学特征,可准确鉴别梗阻类型及梗阻程度。     

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.