Left ventricular hypertrophy and geometry in a population sample of elderly males

BACKGROUND: Recent studies have shown that left ventricular geometric adaptationto hypertension is complex. The spectrum of geometric adaptationsin a general population and its relationship to systolic anddiastolic function has, however, not been investigated. OBJECTIVES AND METHODS: This echocardiographic and Doppler study investigated the relationshipsbetween left ventricular geometric shape (normal, concentricremodelling, concentric hypertrophy and eccentric hypertrophy)and left ventricular systolic and diastolic function in a populationsample of 584 males aged 70 in Uppsala, Sweden. The influencesof hypertension, coronary heart disease and diabetes mellituswere also evaluated. RESULTS: Sixteen percent of the healthy population (n=167) demonstratedthe presence of left ventricular hypertrophy (mainly eccentric).Subjects with hypertension (n=115) showed an increased leftventricular mass (eccentric left ventricular hypertrophy 31%,concentric left ventricular hypertrophy 15%), when comparedwith healthy subjects (P<0.001). Subjects with coronary heartdisease (n=32) without hypertension also showed an increasedleft ventricular mass (most often eccentric) (P<0.05). UsingDoppler determinations of cardiac index, no differences werefound in cardiac index between the geometric groups. Raisedtotal peripheral resistance, increased blood pressure and enlargedleft atrium were found in both concentric and eccentric leftventricular hypertrophy (P<0.01–0.05). Disturbed diastolicfunction was seen with a prolongation of the isovolumic relaxationtime in eccentric (P<0.01) and increased atrial-dependentleft ventricular filling in concentric left ventricular hypertrophy(P<0.05). CONCLUSIONS: Alterations in left ventricular geometry were common in thispopulation-based study of elderly males, both in healthy subjectsand in subjects with hypertension or coronary heart disease.Raised total peripheral resistance and left ventricular diastolicdysfunction were common findings in both concentric and eccentricleft ventricular hypertrophy.     

Proceedings of the Symposium ‘Angiotensin AT1 Receptors: From Molecular Physiology to Therapeutics’: STRUCTURAL CHANGES IN THE RENAL VASCULATURE IN THE SPONTANEOUSLY HYPERTENSIVE RAT: NO EFFECT OF ANGIOTENSIN II BLOCKADE

• 1 There is strong evidence for a renal basis to the development of hypertension in the spontaneously hypertensive rat (SHR). Alterations of the SHR renal vasculature, including the glomerulus, may be involved in the initiation and maintenance of hypertension in this animal model.
• 2 The arterial walls of pre-glomerular vessels of the SHR are hypertrophied compared with WKY vessels. Unlike other vascular beds in the SHR, this hypertrophy is independent of angiotensin II (AngII).
• 3 Glomerular number and volume are similar between SHR and the normotensive Wistar-Kyoto (WKY) rats. These results provide no support for the theory that a reduced filtration surface area within the kidneys of the SHR contributes to the elevated blood pressure in these animals.
• 4 Intrarenal hypertrophy may have similar haemodynamic consequences to clipping of the main renal artery, as in Goldblatt hypertension. Further analysis of the role of pre-glomerular arterial hypertrophy is warranted to determine its involvement in the initiation and maintenance of hypertension in the SHR.

     

Relationship of ambulatory blood pressure monitoring data to echocardiographic findings in haemodialysis patients

BACKGROUND: The present study was performed to assess the value of ambulatoryblood pressure monitoring (ABPM) in determining the adequacyof blood pressure (BP) control, and its relationship to echocardiographicfindings in haemodialysis (HD) patients. METHODS: We studied 40 non-diabetic adult patients who had been on regularHD treatment for a median duration of 43 months. Twenty-four-hourABPM was performed using a non-invasive ABP monitor (Pressurescan,ERKA). Casual BP (cBP) was defined as the average of two measurementsobtained at two HD sessions, one preceding and one followingthe ABP recordings, and was calculated for both the predialysisand postdialysis phases. Two-dimensional and M-mode echocardiographywere performed in each patient to determine interventricularseptal thickness (IVS), left ventricular posterior wall thickness(LVPW), left ventricular fractional shortening (FS), and leftventricular mass index (LVMI) RESULTS: According to average 24-h BP levels, 50% of the patients hadsystolic hypertension (HT) (>139 mmHg), and 72.5% had diastolicHT (>87 mmHg), while only 25% had been diagnosed as HT bycBP measurements (P>0.01 and P>0.0001 respectively). Diurnalvariation in BP was not present in about 80% of the patients.Echocardiography was normal in only four patients (10%). LVMIand LV wall thickness were correlated to ABPM data better thanto cBP measurements. Using stepwise linear regression analysis,LVMI and FVS were positively correlated with systolic BP load(P> 0.0001 and P=0.0001 respectively), and LVPW was positivelycorrelated with night-time systolic BP level (P>0.001). CONCLUSIONS: ABPM is necessary to assess the adequacy of BP control, andis well correlated to end-organ damage of HT in HD patients.     

Hypertension in the elderly: Age- and disease-related complications and therapeutic implications

Summary Effective treatment of hypertension in the elderly requires an understanding of both the progressive course of the disease and the impact of aging on the cardiovascular system, including physiological, genetic, lifestyle, and environmental factors. Review of the literature that has attempted to define the impact of an aging process on cardiovascular structure and function reveals a diversity of findings and interpretations. However, in general, normotensive elderly subjects exhibit the heart and vascular characteristics of muted hypertension, including many features of younger hypertensive patients: cardiac hypertrophy, diminution in resting left ventricular early diastolic filling rate, increased arterial stiffness and aortic impedance, diminution in the baroreceptor reflex, a diminished response to catecholamines and diminished renal blood flow, and an increase in peripheral vascular resistance (PVR). Treatment of elderly hypertensives is more challenging because of the greater likelihood of the presence of concomitant diseases, most importantly, coronary and peripheral atherosclerosis, renal dysfunction, and diabetes mellitus. Isolated systolic hypertension (ISH), the most common form of hypertension in the elderly, has also been clearly shown to be an important predictor of cardiovascular morbidity and mortality, including coronary artery disease, congestive heart failure, and stroke. Treatment of ISH has been shown to lower systolic pressure safely and effectively in the elderly. By reducing PVR, and possibly the arterial stiffness, and thus the early reflected pulse waves, vasodilators, including calcium antagonists, may lower these three components of arterial impedance, and hence lower the arterial load on the heart. The cardiac hypertrophy and reduced left ventricular filling rate associated with hypertension in older individuals can also be ameliorated, to some extent, by calcium channel blockers.Proceedings of a symposium held in Atlanta, Georgia on March 2, 1991.     

氟他胺与2-羟基氟他胺对大鼠前列腺增生的抑制作用(英文)

目的 :研究氟他胺与 2 羟基氟他胺对诱导的前列腺增生大鼠前列腺萎缩和细胞凋亡的作用。方法 :SD大鼠去势 ,皮下注射丙酸睾丸素诱导前列腺增生。前列腺增生大鼠随机分成以下 5组 :对照组、氟他胺组 5 0与 1 0 0mg·kg-1,2 羟基氟他胺组2 5与 5 0mg·kg-1,用药时间为 1 0d。比较前列腺各侧叶湿重 ,以HE染色及TUNEL染色法观察细胞凋亡并计算凋亡发生率。结果 :氟他胺及 2 羟基氟他胺可明显降低前列腺增生大鼠前列腺各侧叶湿重 ,差异有显著意义 ,并可观察到明显的凋亡细胞。结论 :氟他胺与 2 羟基氟他胺可诱导前列腺增生大鼠的前列腺萎缩和细胞凋亡     

血管紧张肽转换酶抑制剂对高血压病人心脏和大动脉的影响

目的 :评价血管紧张肽转换酶 (ACE)抑制剂对原发性高血压病人心脏和大动脉结构和功能的影响。方法 :应用二维超声、超声心动图及自动脉搏波传导速度 (PWV)测定仪观察 16例采用ACE抑制剂培哚普利治疗 (4mg ,po ,qd ;4wk后若血压 >18.6 / 12 .0kPa ,加服吲哒帕胺 2 .5mg ,po ,qd)的原发性高血压病人心脏、大动脉结构和功能的改变 ,分别在治疗前和治疗 12wk后进行上述检测。结果 :收缩压、脉压、颈动脉 股动脉PWV、颈总动脉内膜 中层厚度和左室后壁厚度在 12wk培哚普利治疗后显著降低 [分别为 (2 0 .4±s 1.4 )kPavs (18.0± 1.2 )kPa ,(7.5± 1.1)kPavs (6 .9± 1.2 )kPa ,(10 .5± 1.3)m·s- 1vs (8.6± 1.0 )m·s- 1,(0 .71± 0 .14 )mmvs (0 .5 9± 0 .14 )mm ,(10 .5± 1.0 )mmvs (9.8± 1.0 )mm ,P <0 .0 1或P <0 .0 5 ];颈总动脉横断面顺应性、容积扩张性在治疗前后无显著性差异(P >0 .0 5 )。结论 :培哚普利对心血管系统的影响不仅仅是与血压降低有关 ,药物引起动脉平滑肌松驰 ,对全身和局部肾素 血管紧张肽系统的抑制能有效地改善高血压导致的心脏、血管结构和功能的改变。     

Thirteen-week inhalation toxicity of N,N-dimethylformamide in F344/N rats and B6C3F1 mice.

Male and female F-344 rats and B6C3F1 mice (10/sex/group) were exposed to N,N-dimethylformamide (DMF) by whole body inhalation exposure at 0, 50, 100, 200, 400, or 800 ppm, 6 h/day, 5 days/week, for 13 weeks. A concentration-dependent depression in body weight occurred in rats of both sexes at 400 (6-11%) and 800 ppm (20-22%). In contrast, all weight changes in both sexes of mice were within 10% of controls. No rats died, while 5 mice died from nonexposure-related causes. Relative liver weights were significantly increased at all DMF concentrations in both sexes and both species. Activities of serum sorbitol dehydrogenase (SDH) were statistically increased in male and female rats (200 to 800 ppm) on study days 4, 24, and 91 (13 weeks). Activities of alanine aminotransferase (ALT) and isocitrate dehydrogenase (ICD) were statistically increased in both sexes of rats exposed to 800 ppm DMF at all time points. Cholesterol (CHOL) levels were statistically increased in male and female rats (50-800 ppm) at all sampling time points. Levels of total bile acids (TBA) were statistically increased in both sexes of rats (400-800 ppm) on days 24 and 91. Centrilobular hepatocellular necrosis (minimal to moderate) was seen in rats of both sexes exposed at 400 and 800 ppm, with the lesions more severe in females. Centrilobular hepatocellular hypertrophy (minimal to mild) was found in all groups of DMF-exposed male mice, and in female mice exposed at 100-800 ppm. For male and female rats the no-observed-adverse-effect concentration (NOAEC) for microscopic liver injury was 200 ppm. The NOAEC was 50 ppm for female mice, but an NOAEC based upon the absence of microscopic liver injury was not determined in male mice.     

西红花酸对压力超负荷所致大鼠心肌肥厚的影响

目的研究西红花酸对压力超负荷所致大鼠心肌肥厚的影响。方法腹主动脉部分狭窄术致心肌肥厚,采用试剂盒测定Na⁺-K⁺ ATPase和Ca²⁺-Mg²⁺ ATPase的活力及羟脯氨酸的含量,SDS-PAGE检测MMPs的活力。结果 模型组ATPase活性降低更加明显,羟脯氨酸的含量明显增加,MMPs活力明显增强。西红花酸能显著提高心肌组织的ATPase活力,降低胶原的含量,抑制MMPs的活力。结论西红花酸对压力超负荷所致大鼠心肌肥厚具有一定的改善作用,抑制MMPs的活性可能是其作用机制之一。     

启闭通关汤治疗良性前列腺增生症33例疗效观察

目的　观察自拟启闭通关汤治疗老年良性前列腺增生症 (BPH)的临床疗效。方法　 6 2例BPH患者随机分为 2组。治疗组 33例 ,用自拟启闭通关汤治疗 ;对照组 2 9例 ,用保列治片治疗。 2组均 1个月为 1个疗程 ,3个疗程结束后判断疗效 ,并分别于治疗前和治疗 1、3个疗程时观察记录前列腺症状评分 (IP SS)、生活质量评分、前列腺体积、最大尿流率、残余尿量变化。结果　 2组在治疗 1个疗程时IPSS和生活质量评估均有明显改善 ,治疗 3个疗程较治疗 1个疗程时又有明显改善。治疗 1个疗程时 ,治疗组的最大尿流率已有明显改善 ,残余尿量明显减少 (P <0 .0 5 ) ,但前列腺体积缩小不明显 ,对照组变化均不显著 ,治疗 3个疗程时 ,2组的前列腺体积均明显缩小 (P <0 .0 1)。治疗组总有效率为 81.82 %,对照组为 6 8.97%,治疗组疗效明显优于对照组 (P <0 .0 1)。结论　自拟启闭通关汤能提高最大尿流率 ,减少残余尿量 ,使部分患者的前列腺体积明显缩小 ,未见明显毒副作用 ,综合疗效优于对照组。     

三七总皂苷抗大鼠心肌肥大的作用及其神经机制

目的　探讨三七总皂苷 (PNS)抗腹主动脉缩窄大鼠压力超负荷性心肌肥大的神经机制。方法　①用腹主动脉缩窄法建立心肌肥大模型 ,将大鼠分为假手术对照组、腹主动脉缩窄组及低、中、高剂量组 ,3个剂量组分别每日腹腔注射5 0、10 0和 15 0mgPNS·kg-1。 3wk后处死大鼠检测全心重量/体重 (HW/BW )、左室重量指数 (LVI) ,左心室组织切片HE染色后测心肌纤维直径 (MD)。②细胞内生物电记录技术观察PNS对大鼠星状神经节 (SG)的快兴奋性突触后电位 (f EPSP)、膜电位、膜电阻及对外源性乙酰胆碱引起的膜除极化反应的影响。结果　①高剂量组的HW /BW、LVI及MD显著低于缩窄组 ,P <0 0 1;中剂量组与缩窄组比较MD显著降低 ,P <0 0 5 ;低剂量组与缩窄组比较 ,HW/BW ,LVI和MD三项指标均无显著的变化。②PNS在 0 10～ 0 16g·L-1浓度范围内可使大鼠星状神经节f EPSP可逆性减小 ,PNS还可拮抗高钙对f EPSP的易化作用 ,但对膜电位、膜电阻及外源性ACh引起的膜除极反应无显著的影响。结论　PNS对f EPSP的抑制可能是其抗压力超负荷性心肌肥大的神经机制 ,而抑制作用则是通过突触前机制产生 ,且与拮抗Ca2 + 内流有关。