Plasma levels of atrial natriuretic factor in mild to moderate hypertensives without signs of left ventricular hypertrophy: correlation with the known duration of hypertension

The relationship between plasma atrial natriuretic factor (ANF), blood pressure (BP), age, plasma renin activity (PRA) and urinary sodium excretion was studied in 64 normal subjects (mean age 48.7 +/- 2.1 yrs; BP: 126.5 +/- 1.6/79.5 +/- 0.9 mmHg) and in 104 untreated uncomplicated essential hypertensives (50.8 +/- 1.1 yrs; BP: 164.7 +/- 1.6/105.2 +/- 0.6 mmHg). ANF was measured by radioimmunoassay after extraction on C18 columns. ANF was significantly higher in the hypertensives than in the normal subjects (37.1 +/- 1.2 vs 29.7 +/- 1.5 pg/ml, P less than 0.01). In normals plasma ANF was significantly correlated with age (r = 0.72, P less than 0.001), Na excretion (r = 0.42, P less than 0.001) and PRA (r = -0.71, P less than 0.001) whereas in the hypertensives ANF plasma levels correlated only with systolic (r = 0.46, P less than 0.001) and diastolic (r = 0.51, P less than 0.001) BP. In addition in hypertensive patients, by multivariate linear regression analysis, a significant correlation was found between age, known duration of hypertension and plasma ANF. The partial correlation coefficient between duration of hypertension and plasma ANF was highly significant (r = 0.80, P less than 0.001). These findings suggest that in essential hypertension the level of arterial BP is a main determinant of the ANF plasma values offsetting the ability of other physiological factors to regulate plasma ANF levels.     

Plasma B-type natriuretic peptide reflects left ventricular hypertrophy and diastolic function in hypertension

BACKGROUND: Hypertension is associated with changes in concentrations of vasoactive peptides and procollagen propeptides, but their relationships with left ventricular hypertrophy and cardiac function are unclear. METHODS: We measured plasma levels of atrial natriuretic peptide (ANP), its amino terminal propeptide (NT-proANP), B-type natriuretic peptide (BNP), endothelin-1 (ET-1), and serum levels of the aminoterminal propeptide of type I procollagen (PINP) and the aminoterminal propeptide of type III procollagen (PIIINP) and echocardiographic parameters in 97 patients with hypertension in the Anglo-Scandinavian Cardiac Outcomes Trial. RESULTS: Median values (reference values) of the peptides were: ANP 11.2 (6.9-14.9) pmol/l, NT-proANP 351 (143-311) pmol/l, BNP 1.1 (0.4-7.2) pmol/l, ET-1 8.7 (1.2-5.0) pmol/l, PIIINP 2.8 (1.7-4.2) microg/l and PINP 29 (19-84) microg/l. Plasma BNP levels in patients with left ventricular hypertrophy (1.2 pmol/l) and patients with echocardiographic signs of diastolic dysfunction (1.5 pmol/l) were greater than those in patients without hypertrophy (0.7 pmol/l) and normal diastolic parameters (0.9 pmol/l) (p<0.05). BNP was the only biochemical parameter that independently predicted interventricular septal diastolic diameter (p<0.05), left ventricular mass index (p<0.01) and ratio of the velocity-time integrals of the E and A waves of the mitral inflow in a stepwise logistic regression analysis (p<0.05). CONCLUSIONS: The results show that BNP reflects the remodelling process in hypertension.     

Patients with a hypertensive response to exercise have impaired systolic function without diastolic dysfunction or left ventricular hypertrophy

OBJECTIVES: We sought to determine if a hypertensive response to exercise (HRE) is associated with myocardial changes consistent with early hypertensive heart disease. BACKGROUND: An HRE predicts the development of chronic hypertension (HT) and may reflect a preclinical stage of HT. METHODS: Patients with a normal left ventricular (LV) ejection fraction and a negative stress test were recruited into three matched groups: 41 patients (age 56 +/- 10 years) with HRE (>210/105 mm Hg in men; >190/105 in women), comprising 22 patients with (HT+) and 19 without resting hypertension (HT-); and 17 matched control subjects without HRE. Long-axis function was determined by measurement of the strain rate (SR), peak systolic strain, and cyclic variation (CV) of integrated backscatter in three apical views. RESULTS: An HRE was not associated with significant differences in LV mass index. Exercise performance and diastolic function were reduced in HRE(HT+) patients, but similar in HRE(HT-) patients and controls. Systolic dysfunction (peak systolic strain, SR, and CV) was significantly reduced in HRE patients (p < 0.001 for all). These reductions were equally apparent in patients with and without a history of resting HT (p = NS) and were independent of LV mass index and blood pressure (p < 0.01). CONCLUSIONS: An HRE is associated with subtle systolic dysfunction, even in the absence of resting HT. These changes occur before the development of LV hypertrophy or detectable diastolic dysfunction and likely represent early hypertensive heart disease.     

Fosinopril improves left ventricular diastolic function in young mildly hypertensive patients without hypertrophy

To clarify whether fosinopril monotherapy can improve left ventricular diastolic function (LVDF) in young mildly hypertensives without hypertrophy, we studied 66 patients (pts) with diastolic blood pressure 90–100 mmHg, aged <45 years, with normal 2-dimensional echocardiography (2-D echo), and impaired DF. Impaired DF was defined as a Doppler transmitral early (E) to atrial (A) filling velocity ratio (E/A ratio) <1. Thirty-eight pts were selected for fosinopril monotherapy. Mean age was 36 years. Duration of documented hypertension was 5.4 years. Mean daily dose of fosinopril was 20 mg. Twenty-eight controls were treated with hydrochlorothiazide and hydralazine combination. Sixty-six age- and sex-matched healthy subjects served to establish normal reference values of 2-D and Doppler echo measurements. All hypertensives were treated for 30 months and re-examined 4 weeks after cessation of treatment. The fosinopril-treated group showed improvements in transmitral E (52 ± 8 cm/s, vs. 61 ± 9 cm/s, p < 0.01), A (56 ± 9 cm/s, vs. 47 ± 6 cm/s, p < 0.05), and E/A ratio (0.93 ± 0.16, vs. 1.29 ± 0.18, p < 0.01). Moreover, the early to atrial velocity-time integral ratio (1.31 ± 0.10, vs. 2.24 ± 0.10, p < 0.001) improved. The pulmonary venous flow pattern normalized after fosinopril therapy. LV mass index, relative wall thickness, LV dimension, left atrial dimension, fractional shortening, heart rate, and body mass index did not change. The hydrochlorothiazide-hydralazine combination-treated group did not show an improved diastolic function. It is concluded that long-term fosinopril monotherapy leads to an improvement of impaired LVDF in young mildly hypertensives without hypertrophy.     

氯沙坦联合依那普利对高血压心肌肥厚患者左室舒张功能的影响

目的 观察氯沙坦联合依那普利对高血压心肌肥厚患者左心室舒张功能的影响.方法 采用自身对照设计,36例坚持随访均患者给予氯沙坦50mg/次,每天一次;依那普利10mg/次～20mg/次,每天一次,随访24周,期间比较血压的变化;治疗前后作超声心动图检查,比较心肌厚度及左室舒张功能的改变.结果 与治疗前相比,患者左室后壁舒张末期厚度(LVPWT)、室间隔舒张末期厚度(IVST)、均明显下降(P<0.01);反映左室舒张功能的A/E值亦较治疗前下降(P<0.05);收缩压与舒张压均明显降低(P<0.01). 结论 氯沙坦与依那普利联合用药能有效地控制血压、逆转左室肥厚、改善左心室舒张功能.     

Left ventricular diastolic function in athletes and borderline hypertensives with mild cardiac hypertrophy.

The aim of this study was to evaluate the diastolic function in athletes and in young borderline hypertensives with mild left ventricular hypertrophy. Left ventricular filling was assessed by echo Doppler measurement of transmitral flow velocity in 18 soccer players (age 22 +/- 4 years, left ventricular mass index, LVMI 136 +/- 12 g/m2), in 15 borderline hypertensives (age 21 +/- 3 years, LVMI 137 +/- 9 g/m2), and 20 normotensive subjects (age 22 +/- 4 years, LVMI 93 +/- 10 g/m2) as reference group. We found that left ventricular filling profile was similar in borderline hypertensives, in athletes and in normotensive subjects. These findings suggest that, at least in the early stage, mild cardiac hypertrophy secondary to borderline blood pressure elevation is characterized by indexes of diastolic function not different from those found in athletes with physiological hypertrophy.     

Relation of atrial natriuretic peptides to left ventricular systolic and diastolic function in heart failure

BACKGROUND: Plasma concentrations of atrial natriuretic peptides are correlated with atrial pressures, as are left ventricular ejection fraction and left ventricular filling abnormalities. AIMS: This study investigated the relation of atrial natriuretic peptides to both left ventricular systolic and diastolic function in heart failure. METHODS: Plasma concentrations of atrial natriuretic peptide and N-terminal pro-atrial natriuretic peptide were measured in 63 patients with chronic heart failure and left ventricular systolic dysfunction. According to Doppler transmitral flow measurements, 19 patients had a restrictive and 44 patients had a non-restrictive left ventricular filling pattern. RESULTS: Plasma concentrations of atrial natriuretic peptide and N-terminal pro-atrial natriuretic peptide were higher in patients with a restrictive filling pattern than in patients with a non-restrictive filling pattern (197 vs. 75 pmol/l, P<0.0001 and 1.14 vs. 0.45 nmol/l, P<0.0001). In univariate analysis, atrial natriuretic peptide and N-terminal pro-atrial natriuretic peptide correlated with deceleration time, E/A ratio and left ventricular ejection fraction. In multivariate analysis, both peptides appeared independently related to left ventricular ejection fraction and left ventricular filling pattern. CONCLUSION: In patients with chronic heart failure, atrial natriuretic peptides provide information on left ventricular systolic as well as diastolic function.     

Treatment of hypertension with perindopril reduces plasma atrial natriuretic peptide levels, left ventricular mass, and improves echocardiographic parameters of diastolic function

BACKGROUND: Hypertension is a major independent risk factor for cardiac deaths, and diastolic dysfunction is a usual finding during the course of this disease. HYPOTHESIS: This study was designed to investigate the effects of chronic therapy with perindopril on left ventricular (LV) mass, left atrial size, diastolic function, and plasma level of atrial natriuretic peptide (ANP) in patients with hypertension. METHODS: Twenty four patients who had not been previously taking any antihypertensive medication and without prior history of angina pectoris, myocardial infarction, congestive heart failure, dysrhythmias, valvular heart disease, or systemic illnesses received 4-8 mg/day of perindopril orally. Echocardiographic studies were acquired at baseline and 6 months after the initiation of therapy. RESULTS: Systolic and diastolic blood pressure decreased from 174 +/- 19.7 and 107.5 +/- 7.8 mmHg to 134 +/- 10.6 and 82 +/- 6.7 mmHg, respectively (p < 0.001). Left ventricular mass decreased from 252.4 +/- 8.3 to 205.7 +/- 7.08 g and left atrial volume from 20.4 +/- 5.1 to 17.6 +/- 5.2 ml, respectively (p < 0.001). Transmitral Doppler early and atrial filling velocity ratio (E/A) increased from 0.69 +/- 0.06 to 0.92 +/- 0.05 m/s and plasma ANP level decreased from 71.9 +/- 11.7 to 35.3 +/- 7.8 pg/ml (p < 0.001). Reduction of LV mass correlated positively with a reduction in ANP levels (r = 0.66, p < 0.0005). CONCLUSIONS: Perindopril caused a significant reduction of LV mass, left atrial volume, and plasma ANP levels, as well as improvement in Doppler parameters of LV filling in this group of patients with hypertension.     

Heart rate variability and left ventricular diastolic function in patients with borderline hypertension with and without left ventricular hypertrophy

The relationships between heart rate variability (HRV), left ventricular mass and diastolic function in borderline hypertensive patients (BHT) were evaluated. 24 h Holter electrocardiogram (ECG) and blood pressure (BP) monitoring, M and 2 D echocardiogram and Doppler analysis in 42 BHT with and without left ventricular hypertrophy (LVH) and in 20 normotensive controls were assessed. From 24-h ECG, time domain indexes of HRV were calculated. Standard Deviation of all Cycles (SDNN) and Standard Deviation of the means of heart periods over five-minute intervals (SDANN) were significantly reduced in BHT with LVH but not in BHT without LVH. No significant differences of short-term variability measures were detectable, although a progressive decrease among control subjects and BHT with and without LVH was observed. Diastolic left ventricular compliance evaluated by early to late transmitral flow velocity ratio (E/A ratio) significantly declined from normotensive subjects to BHT with LVH. There was a significant positive correlation between E/A and SDNN and SDANN throughout all studied groups. This indicates that BHT with LVH has a reduced HRV compared to other groups. This impairment is probably related to left ventricular mass and left ventricular filling abnormalities.     

Silent myocardial ischaemia in treated hypertensives with and without left ventricular hypertrophy

BACKGROUND: Silent ischaemia has been reported to be associated with an increased risk of myocardial infarction and sudden death in a wide range of patient groups. The aim of this study was to examine the prevalence of silent ischaemia in hypertensive patients with and without left ventricular hypertrophy (LVH). METHODS: Twenty hypertensive patients participating in the Anglo-Scandinavian Cardiac Outcomes Trial with echocardiographic LVH (11 males, nine females), and 20 age, sex, blood pressure, and drug treatment-matched hypertensive patients without LVH underwent 24-h combined ambulatory blood pressure and electrocardiographic (ECG) monitoring. Ischaemic events were defined by the 'rule of 3 x 1'-asymptomatic ST-depression >/= 1 mm (0.1 mV), lasting at least 1 min, and with a duration of at least 1 min between two events. RESULTS: Thirteen patients with LVH had ischaemic events, whilst only four without LVH demonstrated ischaemia. Median numbers of events (seven versus zero; P < 0.01) and median total ischaemic area (0.25 versus 0 mV*min/day; P < 0.01) were significantly increased amongst hypertensive patients with LVH by comparison to those without LVH. CONCLUSION: Despite similar levels of established risk factors for atherosclerotic coronary artery disease, the prevalence of silent ischaemia was markedly increased amongst hypertensive patients with LVH by comparison to those with normal left ventricular dimensions. Ambulatory ECG monitoring may have a use in the identification of those at greatest risk of cardiovascular complications and sudden death, amongst hypertensive patients with persistent cardiac hypertrophy despite anti-hypertensive therapy.     

应用多普勒组织成像技术评价原发性高血压左室舒张功能及其相关因素

目的:应用多普勒组织成像技术(DTI)探讨原发性高血压(EH)左室舒张功能的特点,同时检测血中心钠素(ANP)、脑钠素(BNP)的变化,分析两者与左室舒张功能的关系。方法:对照组20例,EH患者(EH组)61例,均行常规超声及DTI检查,EH患者根据左室质量指数(LVMI)分为左室心肌肥厚(LVH)亚组和无 LVH(NLVH )亚组。DTI测量二尖瓣侧环心肌舒张早期峰值运动速度(e)、晚期峰值运动速度(a)及其比值(e/a),测量二尖瓣瓣尖水平舒张早期的最大流速(E0)、舒张晚期的最大流速(A)及 E0 与A流速的比值E0/A。入选病例均测定血浆ANP、BNP浓度。结果:与对照组相比,EH患者E0/A、e/a减小,LVH亚组减小更明显;与对照组相比,EH血浆 ANP、BNP浓度升高, LVH升高更明显; E0/A、e/a比值与 ANP 呈负相关( r = - 0.56和 r = -0.60, 均P<0.01),与BNP呈负相关( r=-0.62和 r=-0.65,均 P<0.01)。结论:血浆 ANP、BNP与应用DTI技术评价的EH左室舒张功能均有较好相关性。     

Hemodynamic and plasma atrial natriuretic peptide responses to acute digitalis therapy in patients with normal and impaired left ventricular function.

BACKGROUND: Digitalis has a long history in the treatment of heart failure but its effects on cardiac hemodynamics and neurohormonal modulation are not well characterized. AIMS: The purpose of this study was to evaluate the relationship between atrial natriuretic peptide (ANP) and the hemodynamic responses to acute digitalis administration in patients with normal and impaired left ventricular function (LVD). METHODS AND RESULTS: Thirty patients were enrolled in the study, 20 with LVD (LVEF=22+/-8%) and 10 control subjects (LVEF=77+/-10%). Hemodynamics and plasma ANP concentrations were measured supine and with leg elevation before and after digitalis. In patients with normal ventricular function, the hemodynamic stress of leg elevation in the pre-digitalis state resulted in significant (P<0.05) increases in PAWP and MPAP. Digitalis administration in the supine position produced reductions in heart rate, PAWP, MPAP and CI; SVR was increased. In LVD patients leg elevation further increased PAWP, RAP and MPAP. Digitalis in the supine position, however, reduced RAP, MPAP and PAWP and increased CI. These improved hemodynamics were preserved during the stress of leg elevation. Leg elevation following digitalis resulted in increased ANP concentrations despite decreased cardiac filling pressures. CONCLUSIONS: Acute digitalis administration results in hemodynamic improvement in LVD patients which may in part result from digitalis stimulated release of myocardial ANP under conditions of hemodynamic stress.     

脑钠肽联合组织多普勒检查对老年高血压患者左室肥厚及舒张功能受损的评估

目的 探讨老年原发性高血压患者左室肥厚(LVH)及舒张功能与脑钠肽(BNP)水平的关系.方法 140例老年原发性高血压患者,其中左室肥厚(LVH)组69例,非左室肥厚(NLVH)组71例,健康对照组50例.测定各组BNP浓度.常规脉冲多普勒测量二尖瓣口舒张早期血流速度(E)、舒张晚期血流速度(A),计算E/A值.应用定量组织速度成像(QTVI)技术测量左室壁二尖瓣环6个位点(侧壁和后间隔、前壁和下壁、前间隔和后壁)处的舒张早期峰值运动速度(Em)、舒张晚期峰值运动速度(Am),计算Em/Am值,同时计算6个位点平均速度(MEm、MAm)、MEm/MAm值及E/MEm值.比较3组间舒张功能指标的变化,以及BNP浓度与超声指标的关系.结果 高血压NLVH组、LVH组E/MEm(11.3±1.83、15.7±1.45)及BNP浓度[(61.64±37.18)ng/L、(138.65±30.23)ng/L]较对照组升高(P＜0.05及P＜0.01);MEm[(6.32±0.94)cm/s、(4.29±0.91)cm/s]及MEm/MAm值(0.76±0.19、0.51±0.11)较对照组减低(P＜0.05及P＜0.01);高血压组BNP浓度与E/A、MEm、MEm/MAm值显著负相关(r=-0.294、r=-0.387、r=-0.422,均P＜0.01),与LVMI及E/MEm值显著正相关(r=0.342及r=0.501,均P＜0.01).结论 高血压患者无论有无左室肥厚均有舒张功能减低,而LVH患者左室舒张功能障碍更为严重.联合血浆BNP浓度和超声指标有助于准确评估老年高血压患者左室肥厚和舒张功能.

Abstract：

Objective To investigate the clinical values of brain natriuretic peptide (BNP) in combination with TDI in diagnosing left ventricular hypertrophy (LVH) and impaired diastolic function in elderly hypertensive patients. Methods The 140 elderly hypertensive patients were divided into LVH group (n=69) and NLVH group (n=71). Control group consisted of 50 normal subjects. Plasma BNP level and index of echocardiography, including mitral peak flow velocity during early and late diastole (E, A), ratio of E/A, average peak velocities of six LV wall sites at mitral annuluses during early and late diastole (MEm, MAm), ratios of MEm/MAm and E/MEm were measured in all patients. The correlation of plasma BNP level with cardiac ultrasonographic findings was also examined. Results The level of BNP [(61.64±37.18)ng/L, (138. 65±30. 23)ng/L] and the ratio of E/MEm (11.3±1.83, 15.7±1.45) were significantly higher in NLVH group and LVH group than in normal group (P＜0. 05 or P＜0. 01). MEm [(6.32±0. 94)cm/s, (4.29±0. 91)cm/s]and MEm/MAm (0.76±0.19, 0.51±0. 11) were significantly lower in NLVH and LVH group than in normal group (P＜0.05 or P＜0. 01). The BNP level was negatively correlated with E/A, MEm and MEm/MAm (r=- 0. 294, r= 0. 387 and r= 0. 422, all P＜0. 01), and was positively correlated with LVMI and E/MEm (r=0.342, r=0.501, all P＜0.01). Conclusions Left ventricular diastolic function is impaired in elderly hypertension patients regardless of LVH or NLVH.Plasma BNP level in combination with echocardiography parameter is accurate to evaluate the LVHand impaired diastolic function in elderly hypertensive patients.     

老年高血压病人左室肥厚与左室舒张功能的关系

目的：研究老年高血压病人左室肥厚与左室舒张功能各参数的关系,探讨在老年人左室肥厚对左室舒张功能的影响。方法：用彩色多普勒超声心动图测量101例老年高血压病人左心室结构及舒张功能参数。结果：101例高血压病人中,左室肥厚组（48例）的左房内径指数（LADI）、等容舒张时间（IVRT）、舒张期二尖瓣E波减速时间（EDT）显著大于左室正常组（53例,P〈0．05～〈0．01）．多元逐步回归分析发现,左室质量指数（LVMI）与左房射血分数（LAEF）、LADI、IVRT和EDT有明显的相关关系（r分别为0．213,0．251．0．450．0．338．P〈0．05～0．001）结论：老年高血压病人的左室增厚可进一步降低左室舒张功能。     

苯那普利对原发性高血压患者血浆内皮素及心钠素的影响

目的：测定原发性高血压（EH）患者血浆内皮素（ET）及心钠素（ANP）,并进行治疗前后对比研究。方法：对36例EH用苯那曾利治疗3周,于治疗前1天及治疗后当天,用放免法测定ET及ANP,并与25例健康者作比较。结果：患者ET及ANP均高于正常对照组;ET含量且随病情加重而明显增高,Ⅰ、Ⅱ、Ⅲ期患者间比较差异有显著性（P＜0．01）;EH患者经苯那普利治疗后ET及ANP均明显降低（P＜0．05及P＜0．01）。结论：ET及ANP在EH发病中起着重要作用,转换酶抑制剂是治疗EH较为理想的药物。     

Beta-adrenergic receptor density and function in left ventricular hypertrophy in young essential hypertensives

A sympathetic overactivity has been reported in the early stages of essential hypertension and has been involved in the pathogenesis of left ventricular hypertrophy (LVH) in essential hypertension. The state of beta2-adrenergic receptors as related to the presence of this complication was investigated in a group of 15 essential hypertensive patients and compared to 10 normotensive control subjects. Left ventricular mass index was determined by bidimensional echocardiography. Plasma catecholamine levels were measured by a radioenzymatic assay. beta2-adrenoceptor density was measured in intact lymphocytes by radioligand binding assay, using the hydrophilic ligand CGP 12177. beta2- adrenoceptor function was assessed by measuring intracellular cAMP levels in isoproterenol-stimulated lymphocytes. Left ventricular mass index (P < 0.05), body mass index (P < 0.01), plasma noradrenaline levels (P < 0.05) and beta2-adrenoceptor density (P < 0.05) were higher in hypertensives than in controls. Left ventricular mass index correlated with body mass index both in normotensives and hypertensives, as well as with plasma noradrenaline levels only in normotensives. Left ventricular mass index also showed a positive correlation with mean arterial pressure and an inverse relationship with beta2-adrenoceptor density and response only in hypertensive patients. In conclusion, left ventricular hypertrophy in young essential hypertensives is associated to a reduced beta2-adrenoceptor density and function, probably as a compensating mechanism of the hypertrophied myocardiocyte secondary to the increased sympathetic outflow.Journal of Human Hypertension (2000) 14, 17-21.     

Patterns of diastolic dysfunction in left ventricular hypertrophy.

The relative sensitivities of and interrelations between different measurements of diastolic function were studied in 50 patients with left ventricular hypertrophy diagnosed on anatomical grounds. Isovolumic relaxation time, the interval from minimum cavity dimension to mitral valve opening and relative dimension increase during this period, and the peak rate of dimension increase and wall thinning during rapid ventricular filling were measured by digitised M mode echocardiography. The relative heights of peak early diastolic and atrial velocities (a/E) and the time for decline of early diastolic velocity to half its peak value (velocity half time) were measured on continuous wave and pulsed Doppler and the relative height of the "a" wave was measured by apexcardiogram. All sets of values except those of the interval from minimum dimension to mitral opening were unimodally distributed, and all differed significantly from those in 20 age matched controls. The relative height of the "a" wave on the apexcardiogram (90% values were abnormal) was the most sensitive method of studying left ventricular diastolic function and peak rate of dimension increase was the least sensitive. Though none of the correlations was high, there were individual associations between peak rate of dimension increase, a/E, peak wall thinning rate, and velocity half time, and independently between delay in mitral valve opening and dimension change during this period. Other values seemed to be independent of one another, suggesting a different physiological basis. It is concluded that these various abnormal values do not reflect a single underlying disturbance of diastolic function. There are at least four possible discrete abnormalities: prolongation of isovolumic relaxation; incoordination during isovolumic relaxation; reduced rate of rapid filling; and an increase in the relative amplitude of the "a" wave probably caused by increased passive stiffness. These may be present singly or in combination in any patient.     

Right ventricular hypertrophy causes impairment of left ventricular diastolic function in the rat

Right ventricular (RV) pressure overload causes right ventricular hypertrophy in several types of pulmonary and congenital heart diseases. The associated cardiac dysfunction has generally been attributed to alterations in RV function. However, due to global neurohormonal adaptations and mechanical ventricular interaction left ventricular (LV) function could be affected as well.Therefore,LV function, RV function and their interaction were studied in rats with monocrotaline (MCT)-induced RV hypertrophy and control rats. MCT (30 mg/kg) was used to induce pulmonary hypertension, which resulted, after 28 days, in marked RV hypertrophy (RV-weight: control 220 ± 15,MCT 437 ± 34mg,p < 0.05). In Langendorff-perfused hearts with balloons inserted in both the LV and the RV, the diastolic pressure-volume relations showed increased stiffness, and relaxation was prolonged in the LV and RV in the MCT group compared to controls. In the MCT group, developed pressures were increased only in the RV. An increase of LV volume increased RV diastolic pressure to a similar extent in both groups. However, an increase in RV volume did not affect LV diastolic pressure in controls, but significantly increased LV diastolic pressure in the MCT group. LV and RV developed pressure-volume relations were not affected. Calculated circumferential end-diastolic wall stresses (σ) were larger in the MCT group (LV-σ: 0.55 ± 0.02, RV-σ: 1.94 ± 0.30 kN/m², both p< 0.05 to control) compared to controls (LV-σ: 0.34 ± 0.06,RV-σ: 1.23 ± 0.46 kN/m2). In the MCT group, collagen content was increased in the LV, septum and RV compared to controls. In conclusion, structural changes of the RV and LV result in depressed LV diastolic function during RV hypertrophy.