The effect of acutely induced hypervolemia on resistance to pulmonary blood flow and pulmonary arterial compliance in patients with chronic obstructive lung disease

The presence of alveolar hypoxia and respiratory acidemia in patients with chronic obstructive lung disease alters the normal relation between pulmonary arterial and left heart pressures at the end of diastole; usually these pressures are the same. With vasoconstriction of the small pulmonary arteries the pulmonary arterial diastolic pressure rises, whereas the mean wedge pressure remains unchanged. Thus, a pressure gradient across the pulmonary circulation appears at the end of diastole representing an increased resistance to pulmonary blood flow. The magnitude of this gradient is closely related to the systemic arterial blood oxyhemoglobin saturation, which is used as an index of alveolar oxygen tension, and to the blood hydrogen ion concentration. In the present study acutely induced hypervolemia caused striking alterations in mean wedge pressure and blood flow. However, the diastolic gradient did not change. The pulmonary diastolic pressure gradient reflects the degree of resistance to pulmonary blood flow regardless of the level of the left heart pressure or the cardiac output. On the other hand, left heart pressure does contribute to the level of the pulmonary arterial diastolic pressure.The pulse pressures recorded in the elastic pulmonary arteries reflect their compliance characteristics and the effect of stroke volume imposed upon them. We have assessed compliance indirectly by examining the relationships between pulmonary arterial systolic pressure, diastolic pressure and stroke volume. The compliance characteristics of the elastic arteries in patients with chronic obstructive lung disease do not differ from normal before or during acutely induced hypervolemia.     

Echocardiographic functions and blood pressure levels in children and young adults from a biracial population: the Bogalusa Heart Study

M-mode echocardiograms were obtained on 651 healthy subjects, 7-22 years of age, whose diastolic blood pressure levels remained in the same height-, race-, and sex-specific decile during two biannual examinations. Echocardiographic measures of heart size and dynamics were compared across the total blood pressure distribution. Left ventricular stroke volume, cardiac output and ejection fraction, minor axis shortening, velocity of circumferential fiber shortening, and peripheral vascular resistance were correlated with blood pressure levels. There were positive correlations (p less than .001) of cardiac output and stroke volume with both systolic and diastolic blood pressure levels. Left ventricular output and stroke volume were associated with measures of body size, especially height, weight, ponderal index, and body surface area (p less than .001). The left ventricular output and stroke volume increased with age and with systolic blood pressure quintiles in the four race-sex groups. With adjustment for systolic blood pressure and measures of body size, white males had greater cardiac output (1.25 l/minute for ages 18-22 years, p = .01) and stroke volume than black males. Black males had higher peripheral resistance (4.5 mm Hg/(l/minute), p = .01) than whites. These results suggest that different hemodynamic mechanisms operate in the early phase of hypertension in blacks vs. whites in this population.     

Is Diastolic Hypertension an Independent Risk Factor for Stroke in the Presence of Normal Systolic Blood Pressure in the Middle-aged and Elderly?

In a prospective population-based study from the Copenhagen City Heart Study, the role of diastolic blood pressure as an independent risk factor of stroke, in the presence of normal systolic blood pressure, was assessed in 6,545 subjects aged 50 to 80 years. Follow-up was 12 years. Subjects were divided into various blood pressure categories according to both diastolic and systolic blood pressure. The risk of stroke was assessed using a multivariate Cox proportional hazards model, taking into account various cardiovascular risk factors (age, sex, smoking, diabetes mellitus, body mass index, and levels of serum cholesterol). After adjustment for risk factors, only subjects with elevated systolic blood pressure had a significantly increased risk of future stroke. The risk of stroke according to blood pressure categories further reflected increasing levels of pulse pressure, with the highest risk of stroke in subjects with the greatest pulse pressure. We conclude that systolic blood pressure is a better predictor of stroke than is diastolic blood pressure, and question whether diastolic blood pressure, in the presence of normal systolic blood pressure, is an independent risk factor for stroke in the middle-aged and elderly.     

我国中年人群脉压对于心血管病事件发病的预测价值

目的 研究在中国中年队列人群中，基线脉压（PP）对冠心病和脑卒中发病的预测价值。方法 中美心血管病和心肺疾病流行病学合作研究于1983－1984年对北京和广州工人和农民人群10076人进行了心血管病危险因素的基线调查。按照统一的随访方案和诊断标准对冠心病和脑卒中事件的发病进行随访登记。到1997年底，平均随访13年，共发生冠心病事件72例，脑卒中事件259例。按PP的4分位组计算年龄性别调整发病率（1／10000人年）和RR值。用Cox比例风险模型调整多项危险因素后分析，PP于冠心病和脑卒中发病的相对危险。结果 冠心病和脑卒中事件的年龄性别调整发病均随PP的4分位而增高，最高和最低4分位组相比，冠心病发病的相对危险为4．68，脑卒中发病的相对危险为6．83。多因素Cox回归显示，PP增加一个标准差，冠心病和脑卒中发病的相对危险是1．54和1．67，低于相应收缩压（SBP）的1．69和2．03，以及舒张压（DBP）的1．61和2．17。在多因素模型中同时控制SBP，则PP和冠心病和缺血型卒中的关联不再显，而与脑卒中，尤其是出血型卒中呈显负关联。而同时控制DBP，则PP和DBP均与冠心病和脑卒中发病呈显正关联。结论 在中国中年人群中，PP虽然对冠心病和脑座中发病呈显正关联，但预测价值低于SBP和DBP。在中年人群高血压防治中，除重视SBP和P，控制DBP增高对预防脑卒中有重要意义。     

Blood pressure and cardiac output during exercise: a longitudinal study of children undergoing repair of coarctation

Data were examined from 21 children who underwent graded exercise studies prior to and within 5 years after repair of coarctation. A control group of 10 normal children was also studied longitudinally on two occasions. The exercise was performed on an upright bicycle ergometer using a continuous graded exercise protocol. Parameters measured were heart rate, systolic and diastolic blood pressure at rest, and these pressures at the maximal voluntary exercise level. In addition, a subset of patients and controls had measurement of cardiac output by a modified acetylene rebreathing technique. Results indicate that coarctation patients had significant elevation of systolic and diastolic blood pressures at rest (p less than 0.001 for both) and with exercise (p less than 0.02 for both) prior to surgery. The group mean values for systolic and diastolic blood pressure did not differ from control values after surgery; however, some individuals continued to have hypertension at rest when compared to population-based norms. Heart rate, cardiac index, and stroke volume index did not differ from those of control subjects either at rest or during exercise before or after surgery. In conclusion, a group of coarctation patients studied longitudinally demonstrated marked improvement in both systolic and diastolic hypertension after surgery. The findings of normal cardiac output and stroke volume indices may have implications for the etiology of postoperative hypertension.     

应用时间-空间相关成像技术评估妊娠期高血压疾病胎儿心功能

目的 探讨时间-空间相关成像(spatio-temporal image correlation,STIC)技术评价妊娠期高血压疾病胎儿心功能的临床应用。方法 运用STIC技术采集110例正常孕妇胎儿及84例妊娠期高血压疾病（PIH）孕妇胎儿心动周期图像,通过VOCAL功能获得容积参数,包括左、右心室舒张末期容积（LVEDV、RVEDV）,左、右心室收缩末期容积（LVESV、RVESV）,计算出左、右心室每搏量（LVSV、RVSV）,左、右心室射血分数（LVEF、RVEF）,左、右心室心排出量（LVCO、RVCO）。根据孕妇高血压严重程度及临床症状分为:PIH I组(孕妇血压轻度升高或轻度子痫前期):即孕妇妊娠20周后第1次出现血压升高,140/90 mmHg≤血压值<160/110 mmHg(1 mmHg=0.133 kPa),间隔6 h以上,至少出现过两次,尿蛋白弱阳性;PIH II组(重度子痫前期):血压≥160/110 mmHg,和(或)尿蛋白阳性或者强阳性(++),或伴有微血管溶血、神经系统及肺水肿等症状。结果 ①与对照组相比,PIH I组胎儿左、右EDV、ESV、SV、EF、CO差异均无统计学意义;②与对照组、PIH I组相比,PIH II组胎儿的左、右EDV、ESV增大、差异有统计学意义（P<0.05,P<0.01）,PIH II组胎儿的SV、EF、CO均减小,差异有统计学意义（P<0.05,P<0.01）。结论 STIC技术可以评价妊娠期高血压病胎儿心功能的变化。     

Diastolic heart failure: old story, new concepts

Diastolic heart failure refers to a clinical syndrome characterised by symptoms and signs of congestive heart failure, with a normal or subnormal left ventricular (LV) systolic function associated with alterations in LV diastolic function. Diastolic dysfunction is a pathological condition during which the LV is unable to accept a volume of blood coming back from the lungs appropriate to maintain its stroke volume under normal filling pressure. Three eventually associated mechanisms are responsible for such dysfunction: impaired LV relaxation, increased LV stiffness and loss of normal atrial function. Prevention of LV hypertrophic remodelling should decrease the incidence of diastolic heart failure.     

Primary myocardial disease Clinical, hemodynamic and angiocardiographic correlates in fifty patients

Fifty adult patients with primary myocardial disease were studied by clinical, hemodynamic and angiographic means. The patients were divided into two groups on the basis of the diastolic phase of the left ventricular pressure pulse. The 24 patients in Group I had a normal pulse contour or elevated end-diastolic pressure, characterized by a presystolic prominent transmitted a wave. The 26 patients in Group II had abnormal elevation of the entire left ventricular diastolic phase (congestive pattern); in 9 of the 26 this was accompanied by an early diastolic dip and plateau (restrictive pattern). There were no significant differences in age, sex, race or chronic alcoholism between the groups. Patients in Group II had a longer duration of symptoms, increased frequency of third heart sounds, apical systolic murmurs and abnormal left axis deviation.

Patients in Group I had normal resting hemodynamics except for elevation of the filling pressure of the left ventricle (14 patients) and right ventricle (9 patients), as well as a low left ventricular stroke work. Patients in Group II had evidence of biventricular dysfunction accompanied by low cardiac index, mean systolic ejection rate, and left ventricular stroke work. The left ventricular end-diastolic volume was greater in patients in Group II than in those in Group I, and the mean values for both groups were significantly greater than normal (P < 0.001). Forty-two percent of the patients in Group I had a normal end-diastolic volume. The left ventricular wall was thicker in patients in Group I than those in Group II (P < 0.001). The ejection fraction was significantly lower in patients in Group II, and the mean values for both groups were lower than normal. Predominant left ventricular hypertrophy appeared to characterize the condition of patients in Group I, and predominant dilation that of patients in Group II. This was further corroborated by the relations among cavity volume, wall thickness and weight of the ventricle. The patients in Group I had a normal end-diastolic circumferential stress and an elevated tension whereas both these indexes were abnormally elevated in patients in Group II.

Our experience with primary myocardial disease suggests that there is an early latent asymptomatic stage followed by a symptomatic hypertrophic stage (Group I) which progresses to an irreversible stage of dilatation (Group II).     

Experimental investigations on the effect of etilefrinhydrochloride (Effortil) on heart and circulation of animals with partial ischaemic damage of the myocardium (author's transl)

The effect of Etilefrin on the blood flow of normal and partial ischaemic myocardium with heat conductance probes as well as on the ventricular dynamics was investigated on 11 dogs under propiomazine-pentobarbital narcosis. Etilefrin was applied in doses of 0.04 mg/kg bw. and 0.2 mg/kg bw. At low doses, the blood flow was only elevated in normal myocardium, likewise the systolic aortic pressure, the diastolic aortic pressure decreased, the heart frequency was elevated, whereas the systolic pressure in the left ventricle was only slightly increased for a short time, the enddiastolic pressure unchanged, dp/dtmax rose significantly, but the heart minute volume only slightly. At higher doses, elevation of blood flow also appeared in partial ischaemic myocardium, the aortic pressure, systolic and diastolic, decreased considerably at first and then 20 min. p.i. rose to above the control value. The heart frequency was more elevated than at lower doses, the pressures in the left ventricle showed no obvious changes, dp/dtmax and heart minute volume were likewise considerably elevated. Radiological measurements of the ejection fraction and the mean circumferential fiber shortening velocity at higher Etilefrin doses showed also a positive inotropic effect. In consideration of this fact, therapy with Etilefrin appears useful in disturbances of cardiac function and at least shows no contraindication by means of myocardial blood flow.     

Pulse pressure and risk of cardiovascular events in the systolic hypertension in the elderly program.

Pulse pressure has been related to higher risk of cardiovascular events in older persons. Isolated systolic hypertension is common among the elderly and is accompanied by elevated pulse pressure. Treatment of isolated systolic hypertension may further increase pulse pressure if diastolic pressure is lowered to a greater extent than systolic pressure. Little is known regarding pulse pressure as a predictor of cardiovascular outcomes in elderly persons with isolated systolic hypertension, and the influence of treatment on the pulse pressure effect. We assessed the relation between pulse pressure, measured throughout the follow-up period, and the incidence of coronary heart disease (CHD), heart failure (HF), and stroke in 4,632 participants in the Systolic Hypertension in the Elderly Program, a 5-year randomized, placebo-controlled clinical trial of treatment of isolated systolic hypertension in older adults. In the treatment group, a 10-mm Hg increase in pulse pressure was associated with a statistically significant 32% increase in risk of HF and a 24% increase in risk of stroke after controlling for systolic blood pressure and other known risk factors, as well as with a 23% increase in risk of HF and a 19% increase in risk of stroke after controlling for diastolic blood pressure and other risk factors. Pulse pressure was not significantly associated with HF or stroke in the placebo group, nor with incidence of CHD in either the placebo or treatment group. These results suggest that pulse pressure is a useful marker of risk for HF and stroke among older adults being treated for isolated systolic hypertension.     

From left ventricular hypertrophy to congestive heart failure: management of hypertensive heart disease

Other than age, left ventricular hypertrophy (LVH) is the most potent predictor of adverse cardiovascular outcomes in the hypertensive population, and is an independent risk factor for coronary heart disease, sudden death, heart failure and stroke. Although directly related to systolic blood pressure, other factors including age, sex, race, body mass index and stimulation of the renin-angiotensin-aldosterone and sympathetic nervous systems play an important role in the pathogenesis of LVH. LVH involves changes in myocardial tissue architecture consisting of perivascular and myocardial fibrosis and medial thickening of intramyocardial coronary arteries, in addition to myocyte hypertrophy. The physiologic alterations which occur as a result of these anatomical changes include disturbances of myocardial blood flow, the development of an arrhythmogenic myocardial substrate and diastolic dysfunction. The latter is directly related to the degree of myocardial fibrosis and is the hemodynamic hallmark of hypertensive heart disease. When diastolic dysfunction is present, left ventricular end-diastolic pressure increases out-of-proportion to volume and may be elevated at rest or with exertion leading to clinical heart failure. At least one third of heart failure patients in the United States can be considered to have heart failure related to diastolic dysfunction. Compared to heart failure patients with systolic dysfunction, diastolic heart failure patients are more likely to be older, female, and to be hypertensive at the time of presentation. Although it has been assumed that LVH may lead to systolic dysfunction, evidence is lacking that LVH resulting from hypertension is a major risk factor for systolic heart failure independent of coronary artery disease. Treatment of hypertension greatly attenuates the development of LVH and significantly decreases the incidence of heart failure. In patients with established LVH, regression is both possible and desirable and results in a significant reduction in adverse clinical endpoints.     

Pulse pressure in sustained essential hypertension: a haemodynamic study

Central and forearm haemodynamics were studied in 73 middle-aged male subjects: 14 normotensive controls and 59 patients with sustained essential systolic/diastolic hypertension. Hypertensives were divided into two groups: pulse pressure within the normal range (40-60 mmHg; group I) or above 60 mmHg (group II) for the same level of mean arterial pressure (MAP). Indices of systemic and forearm arterial compliance and distensibility for the same age and MAP were reduced to the same extent in group I and II. In contrast, the peak systolic blood flow velocity of the brachial artery, cardiac output (CO) and stroke volume (SV) were significantly greater in group II than in group I. Systemic and forearm vascular resistances were significantly increased in group I but remained within the normal range in group II. The study provided evidence that, in middle age, there is a group of hypertensive patients characterized by a disproportionate increase in pulse pressure for the level of MAP. The elevation of the pulsed component of blood pressure (BP) reflects a relative hyperkinesia with an increase in CO and arteriolar vasodilatation. The subsequent increase in systolic pressure is produced by a combination of reduced arterial distensibility and increased SV.     

Increased stroke volume and aortic stiffness contribute to isolated systolic hypertension in young adults

Isolated systolic hypertension is a common condition in individuals aged older than 60 years. However, isolated systolic hypertension has also been described in young individuals, although the mechanisms are poorly understood. We hypothesized that in young adults, isolated systolic hypertension and essential hypertension have different hemodynamic mechanisms and the aim of this study was to test this hypothesis in a cohort of subjects from The ENIGMA Study. Peripheral and central blood pressure, aortic pulse wave velocity, cardiac output, stroke volume, and peripheral vascular resistance were determined in 1008 subjects, aged 17 to 27 years. Compared with normotensive subjects, those with isolated systolic hypertension had significantly higher peripheral, central, and mean blood pressure, aortic pulse wave velocity, cardiac output, and stroke volume (P<0.001 for all comparisons). However, there were no differences in pulse pressure amplification, heart rate, or peripheral vascular resistance between the two groups. Compared with subjects with essential hypertension, mean pressure, heart rate, and peripheral vascular resistance were all significantly lower in isolated systolic hypertensive subjects, but pulse pressure amplification, aortic pulse wave velocity, cardiac output, and stroke volume were higher (P<0.001 for all comparisons). We have demonstrated that in young adults, isolated systolic hypertension and essential hypertension arise from different hemodynamic mechanisms. Isolated systolic hypertension appears to result from an increased stroke volume and/or aortic stiffness, whereas the major hemodynamic abnormality underlying essential hypertension is an increased peripheral vascular resistance. Long-term follow-up of these individuals is now required to determine whether they are at increased risk compared with age-matched normotensive individuals.     

Left ventricular function at rest and during exercise in acute hypothyroidism

The effect of hypothyroidism on left ventricular function at rest and during exercise was studied in nine patients without demonstrable cardiovascular disease who had had total thyroidectomy and ablative radioiodine treatment for thyroid cancer. Radionuclide ventriculography and simultaneous right heart catheterisation were performed while the patients were hypothyroid two weeks after stopping triiodothyronine treatment (to permit routine screening for metastases) and while they were euthyroid on thyroxine replacement treatment. When the patients were hypothyroid, cardiac output, stroke volume, and end diastolic volume at rest were all lower and peripheral resistance was higher than when they were euthyroid. Pulmonary capillary wedge pressure, right atrial pressure, heart rate, left ventricular ejection fraction, and the systolic pressure:volume relation of the left ventricle, which was used as an estimate of the contractile state, were not significantly different when the patients were hypothyroid or euthyroid. During exercise, heart rate, cardiac output, end diastolic volume, and stroke volume were higher when the patients were euthyroid than when they were hypothyroid. Again, pulmonary capillary wedge pressure, ejection fraction, and the systolic pressure:volume relation were similar in both thyroid states. The data suggest that the alterations in cardiac performance seen in short term hypothyroidism are primarily related to changes in loading conditions and exercise heart rate; they do not suggest that acute thyroid hormone deficiency has a major effect on the contractile properties of the myocardium.     

Arterial and venous compliance in sustained essential hypertension

Arterial and venous compliances are decreased in men with sustained essential hypertension. The reduced arterial compliance acts to maintain systolic pressure and end-systolic stress, thus contributing to the development of cardiac hypertrophy. Since cardiac output remains within the normal range in the hypertrophied hypertensive heart, elevated left ventricular pressures, and therefore increased cardiac filling pressures, are necessary if an adequate stroke volume is to be maintained. In hypertensive persons, reduced venous compliance acts to maintain the filling pressure of the heart in the presence of reduced intravascular volume. In patients with hypertension, even if compliance changes have been initiated by the elevated blood pressure itself, the reduced arterial and venous compliance observed in cross-sectional studies is not simply the mechanical consequence of the elevated blood pressure, but also reflects intrinsic alterations of the vascular wall. Consequently, blood pressure reduction caused by antihypertensive agents is not constantly associated with a reversion of the decreased vascular compliance. Such observations may be of importance in the consideration of cardiovascular morbidity and mortality in patients treated for hypertension.     

Left ventricular function at rest and during exercise in acute hypothyroidism.

The effect of hypothyroidism on left ventricular function at rest and during exercise was studied in nine patients without demonstrable cardiovascular disease who had had total thyroidectomy and ablative radioiodine treatment for thyroid cancer. Radionuclide ventriculography and simultaneous right heart catheterisation were performed while the patients were hypothyroid two weeks after stopping triiodothyronine treatment (to permit routine screening for metastases) and while they were euthyroid on thyroxine replacement treatment. When the patients were hypothyroid, cardiac output, stroke volume, and end diastolic volume at rest were all lower and peripheral resistance was higher than when they were euthyroid. Pulmonary capillary wedge pressure, right atrial pressure, heart rate, left ventricular ejection fraction, and the systolic pressure:volume relation of the left ventricle, which was used as an estimate of the contractile state, were not significantly different when the patients were hypothyroid or euthyroid. During exercise, heart rate, cardiac output, end diastolic volume, and stroke volume were higher when the patients were euthyroid than when they were hypothyroid. Again, pulmonary capillary wedge pressure, ejection fraction, and the systolic pressure:volume relation were similar in both thyroid states. The data suggest that the alterations in cardiac performance seen in short term hypothyroidism are primarily related to changes in loading conditions and exercise heart rate; they do not suggest that acute thyroid hormone deficiency has a major effect on the contractile properties of the myocardium.     

Systolische Hypertonie—Treat or Not to Treat?

HEMODYNAMICS: Elevated diastolic as well as elevated systolic blood pressure substantially contribute to the increase of cardiovascular risk. Conclusive results have proven that lowering diastolic and/or systolic blood pressure can reduce cardiovascular risk. There is evidence that not only the absolute values for diastolic and systolic blood pressure alone but also the pulse pressure as an additional indicator of cardiovascular risk have to be considered. The prevalence of isolated systolic hypertension increases with age. Remodeling of the arterial wall with increase of collagen and decrease of elastic fibers are leading to an impaired arterial compliance. Decreased compliance and acceleration of the pulse wave velocity can elevate systolic and lower diastolic blood pressure. In consequence cardiac stress and pulse pressure will rise. CONCLUSION: There is a strong correlation in elderly patients between cardiovascular mortality and morbidity and systolic blood pressure. Antihypertensive therapy is able to lower cardiovascular event rate in elderly patients with isolated systolic hypertension with a predominant risk reduction for stroke.     

The diastolic blood pressure in systolic hypertension

Because antihypertensive therapy is effective in elderly patients with isolated systolic hypertension, attention has been focused on the systolic blood pressure as a predictor of cardiovascular risk. However, it is a normal diastolic pressure that separates patients with isolated systolic hypertension from those with essential hypertension. The normal diastolic and elevated systolic pressures are largely due to age-related stiffening of the aorta. An indistensible aorta causes the pressure pulse to travel faster than normal, where it is quickly reflected off the peripheral resistance. The reflected wave then returns to the central aorta in systole rather than diastole. This augments the systolic pressure further, increasing cardiac work while reducing the diastolic pressure, on which coronary flow is dependent. The potential harm of further reducing the diastolic pressure with antihypertensive therapy, especially in patients with coronary heart disease, underlies the controversial "J curve." By decreasing the blood pressure, all antihypertensive agents improve aortic distensibility, but no agents do so directly; the nitrates come the closest. Such an agent would be useful because any therapeutic increase in aortic distensibility would decrease systolic pressure without greatly reducing diastolic pressure. The problem is complicated by the suspected inaccuracy of the cuff technique in predicting the aortic diastolic pressure. New noninvasive methods to predict the aortic diastolic pressure may help in the future. At present, the combination of a high systolic and normal diastolic pressure-a widened pulse pressure-seems to be the best predictor of cardiovascular risk in patients with hypertension or heart disease. Patients with isolated systolic hypertension should be treated, but marked diastolic hypotension should be avoided.     

Effect of adaptation to physical loads on the contractile function and mass of the left ventricle of the heart]

Echocardiography was used to examine 20 highly trained athletes and 12 untrained persons at rest and during increasing physical load. It was established that in untrained persons the stroke volume in moderate and large physical loads increases mainly due to an increase in the diastolic output with the systolic output unchanged. In highly trained athletes the stroke volume with an equal load increases due both to growth in the diastolic output and to considerable decrease in the systolic output, i.e., due to the more complete ejection of blood from the cavity of the ventricle. As a result in trained patients a sufficient minute output in physical exertion is attained with less external work of the left ventricle and myocardial tension.     

Schilddrüse und Blutdruck

Thyroid hormones have several well-recognized effects on the vasculature and heart, resulting in characteristic cardiovascular changes in thyroid disease, including an increase in blood pressure. In hyperthyroidism reduced systemic vascular resistance and increased blood volume lead to an enhanced preload, which, in association with reduced afterload, improved contractility, as well as increased β-adrenergic activity, results in isolated systolic hypertension based on enhanced stroke volume and cardiac output. In contrast, hypothyroidism causes increased systemic vascular resistance in association with decreased arterial compliance resulting in elevated diastolic blood pressure. Therefore in the evaluation of arterial hypertension secondary hypertension based on thyroid disease should always be considered, especially given the fact that blood pressure changes in the course of thyroid dysfunction are usually reversible upon adequate treatment of hypo- or hyperthyroidism.