Echocardiographic assessment of the different left ventricular geometric patterns in hypertensive patients

OBJECTIVE: To identiy left ventricular geometric patterns in hypertensive patients on echocardiography, and to correlate those patterns with casual blood pressure measurements and with the parameters obtained on a 24-hour ambulatory blood pressure monitoring. METHODS: We studied sixty hypertensive patients, grouped according to the Joint National Committee stages of hypertension.. Using the single- and two-dimensional Doppler Echocardiography, we analyzed the left ventricular mass and the geometric patterns through the correlation of left ventricular mass index and relative wall thickness. On ambulatory blood pressure monitoring we assessed the means and pressure loads in the different geometric patterns detected on echocardiography RESULTS: We identified three left ventricular geometric patterns: 1) concentric hypertrophy, in 25% of the patients; 2) concentric remodeling, in 25%; and 3) normal geometry, in 50%. Casual systolic blood pressure was higher in the group with concentric hypertrophy than in the other groups (p=0.001). Mean systolic pressure in the 24h, daytime and nighttime periods was also higher in patients with concentric hypertrophy, as compared to the other groups (p=0.003, p=0.004 and p=0.007). Daytime systolic load and nighttime diastolic load were higher in patients with concentric hypertrophy ( p=0.004 and p=0.01, respectively). CONCLUSIONS: Left ventricular geometric patterns show significant correlation with casual systolic blood pressure, and with means and pressure loads on ambulatory blood pressure monitoring.

Experimental myocardial hypertrophy induced by a minimally invasive ascending aorta coarctation

Ascending aorta coarctation was produced by a minimally invasive technique in rabbits. Animal mortality was 5%. Morphometric and hemodynamic parameters were evaluated. A parabiotically isolated heart model was used to assess the hemodynamic parameters. Left ventricular weight/body weight ratio and muscle area showed clear evidence of hypertrophy when compared to control. The hemodynamic changes in the isolated heart model suggested decreased diastolic and systolic function in the coarcted group. The present model produced hypertrophy with low mortality rates as a result of its less invasive nature.

Prevalence of Trypanosoma cruzi antibodies and inflammatory markers in uncompensated heart failure

INTRODUCTION: Heart failure (HF) represents the final stage of chronic chagasic cardiomyopathy (CChC). The diagnosis of CChC is based on the demonstration of anti-Trypanosoma cruzi antibodies (aTcAg) and clinical and epidemiological data. In Venezuela, there are no data about the prevalence of chagasic HF. The aim of this study was to determine the epidemiological, clinical, and inflammatory risk factors associated with seronegative or seropositive HF patients. METHODS: We performed a cross-sectional study in the Venezuelan central-west states among a healthy rural population and in patients admitted to the emergency room with uncompensated HF. RESULTS: The seroprevalence rates of Trypanosoma cruzi antibodies were 11.2% and 40.1% in the healthy population and in HF patients, respectively. Seropositivity in healthy individuals was associated with age, knowledge on triatomine vectors, and having seen wild reservoirs in the house; in HF patients, with contact with the vector and previous clinical diagnosis of Chagas' disease; and in both groups taken together, with age, knowledge on triatomines, and HF. Seropositive patients had prolonged QRS, decreased ejection fraction, and high serum magnesium, all significant as compared with HF seronegative cases. Left atrium enlargement and ventricular hypertrophy were most frequently observed in HF seronegative patients. CRP, IL6, ILβ1, IL2, and FNTα were elevated in 94.5%, 48%, 17.8%, 13.7%, and 6.9% of HF patients, respectively, but only IL2 levels were associated with chagasic HF. CONCLUSIONS: There is a high prevalence of aTcAg in HF patients from the central-west region of Venezuela, and their epidemiological, clinical, and inflammatory features are discreetly different as compared with those of seronegative cases.

Pompe's disease or type IIa glycogenosis

This is the report of a five-month-old child presenting clinical evidence of Pompe's disease: severe hypotonicity, hyporeflexia and congestive heart failure. The ECG showed a short PR interval, the chest radiography disclosed marked cardiomegaly, and the echocardiogram revealed marked left ventricular hypertrophy - the most typical finding of this disease. A skeletal muscle biopsy led to final diagnosis, because in the histopathologic study marked increased glycogen accumulation was evident. Death occurred two months after symptom onset.

Right coronary artery fistula with congestive heart failure in the neonate. Doppler echocardiographic diagnosis and closure with detachable balloon

We report here a case of coronary artery fistula in a neonate with clinical signs of heart failure. The electrocardiogram showed signs of left ventricular hypertrophy and diffuse alterations in ventricular repolarization. Chest X-ray showed an enlargement of the cardiac silhouette with an increase in pulmonary flow. After echocardiographic diagnosis and angiographic confirmation, closure of the fistulous trajectory was performed with a detachable balloon with an early and late successful outcome.

Distribution of cardiac geometric patterns on echocardiography in essential hypertension. Impact of two criteria of stratification

PURPOSE: To evaluate 2 left ventricular mass index (LVMI) normality criteria for the prevalence of left ventricular geometric patterns in a hypertensive population ( HT ) . METHODS: 544 essential hypertensive patients, were evaluated by echocardiography, and different left ventricular hypertrophy criteria were applied: 1 - classic : men - 134 g/m² and women - 110 g/m² ; 2- obtained from the 95th percentil of LVMI from a normotensive population (NT). RESULTS: The prevalence of 4 left ventricular geometric patterns, respectively for criteria 1 and 2, were: normal geometry - 47.7% and 39.3%; concentric remodelying - 25.4% and 14.3%; concentric hypertrophy - 18.4% and 27.7% and excentric hypertrophy - 8.8% and 16.7%, which confered abnormal geometry to 52.6% and 60.7% of hypertensive. The comparative analysis between NT and normal geometry hypertensive group according to criteria 1, detected significative stuctural differences,"( *p < 0.05):LVMI- 78.4 ± 1.50 vs 85.9 ±0.95 g/m² *; posterior wall thickness -8.5 ± 0.1 vs 8.9 ± 0.05 mm*; left atrium - 33.3 ± 0.41 vs 34.7 ± 0.30 mm *. With criteria 2, significative structural differences between the 2 groups were not observed. CONCLUSION: The use of a reference population based criteria, increased the abnormal left ventricular geometry prevalence in hypertensive patients and seemed more appropriate for left ventricular hypertrophy detection and risk stratification.

Autonomic Modulation of the Heart in Systemic Arterial Hypertension

OBJECTIVE: To analyze the heart rate variability in patients with mild to moderate systemic arterial hypertension. METHODS: Thirty-two healthy (group I) and 70 systemic arterial hypertensive (group II) individuals, divided according to age (40 to 59 and 60 to 80 years old, respectively) and with a similar distribution by sex were studied. Thirty-one had left ventricular hypertrophy (LVH), 22 were overweight, and 16 had Type II diabetes mellitus. Smoking, alcohol ingestion, and sedentary habits were the same between groups. Variability in heart rate was analyzed in the time domain, using standard deviations of normal RR intervals (SDNN) and the differences between maximal brady- and tachycardia (D-BTmax) during sustained inspiration. Analysis of the frequency band of the power spectrum between 0.05 and 0.40 Hz at rest and during controlled respiration was chosen for analysis of the frequency domain. RESULTS: In both time and frequency domains, variables were lower in group II than in group I. Within groups, statistically significant variables were only found for individuals in the 40 to 59 year old group. The presence of LVH, overweight, or diabetes mellitus did not influence the variability in heart rate to a significant extent. CONCLUSION: Variability in heart rate was a valuable instrument for analyzing autonomic modulation of the heart in arterial hypertension. The autonomic system undergoes significant losses in cardio-modulatory capacity, more evident in subjects between 40 and 59 years old. In those over 60 years old, reduced variability in heart rate imposed by aging was not significantly influenced by the presence of systemic arterial hypertension.

Acute Myocardial Infarction: The First Manifestation of Ischemic Heart Disease and Relation to Risk Factors

OBJECTIVE: To assess the association between cardiovascular risk factors and acute myocardial infarction as the first manifestation of ischemic heart disease, correlating them with coronary angiographic findings. METHODS: We carried out a cross-sectional study of 104 patients with previous acute myocardial infarction, who were divided into 2 groups according to the presence or absence of angina prior to acute myocardial infarction. We assessed the presence of angina preceding acute myocardial infarction and risk factors, such as age >55 years, male sex, smoking, systemic arterial hypertension, lipid profile, diabetes mellitus, obesity, sedentary lifestyle, and familial history of ischemic heart disease. On coronary angiography, the severity of coronary heart disease and presence of left ventricular hypertrophy were assessed. RESULTS: Of the 104 patients studied, 72.1% were males, 90.4% were white, 73.1% were older than 55 years, and 53.8% were hypertensive. Acute myocardial infarction was the first manifestation of ischemic heart disease in 49% of the patients. The associated risk factors were systemic arterial hypertension (RR=0.19; 95% CI=0.06-0.59; P=0.04) and left ventricular hypertrophy (RR=0.27; 95% CI=0,.8-0.88; P=0.03). The remaining risk factors were not statistically significant. CONCLUSION: Prevalence of acute myocardial infarction as the first manifestation of ischemic heart disease is high, approximately 50%. Hypertensive individuals more frequently have symptoms preceding acute myocardial infarction, probably due to ventricular hypertrophy associated with high blood pressure levels.

Vector electrocardiographic alterations after percutaneous septal ablation in obstructive hypertrophic cardiomyopathy: possible anatomic causes

OBJECTIVE: Analyze the dromotropic disturbances (vector-electrocardiographic), and the possible anatomic causes, provoked by selective alcohol injection in the septal branch, for percutaneous treatment, of obstructive hypertrophic cardiomyopathy. METHODS: Ten patients with a mean age of 52.7 years underwent percutaneous septal ablation (PTSA) from october 1998; all in functional class III/IV). Twelve-lead electrocardiogram was performed prior to and during PTSA, and later electrocardiogram and vectorcardiogram according to Frank's method. The patients were followed up for 32 months. RESULTS: On electrocardiogram (ECG) prior to PTSA all patients had sinus rhythm and left atrial enlargement, 8 left ventricular hypertrophy of systolic pattern. On ECG immediately after PTSA, 8 had complete right bundle-branch block; 1 transient total atrioventricular block; 1 alternating transient bundle-branch block either right or hemiblock. On late ECG 8 had complete right bundle-branch block confirmed by vectorcardiogram, type 1 or Grishman. CONCLUSION: Septal fibrosis following alcohol injection caused a predominance of complete right bundle-branch block, different from surgery of myotomy/myectomy.

Female alcoholics: electrocardiographic changes and associated metabolic and electrolytic disorders

OBJECTIVE: To identify the electrocardiographic changes and their associations with metabolic and electrolytic changes in female alcoholics. METHODS: The study comprised 44 female alcoholics with no apparent physical disorder. They underwent the following examinations: conventional electrocardiography; serologic tests for syphilis, Chagas' disease, and hepatitis B and C viruses; urinary pregnancy testing; hematimetric analysis; biochemical measurements of albumin, fibrinogen, fasting and postprandial glycemias, lipids, hepatic enzymes, and markers for tissue necrosis and inflammation. RESULTS: Some type of electrocardiographic change was identified in 33 (75%) patients. In 17 (38.6%) patients, more than one of the following changes were present: prolonged QTc interval in 24 (54.5%), change in ventricular repolarization in 11(25%), left ventricular hypertrophy in 6 (13.6%), sinus bradycardia in 4 (9.1%), sinus tachycardia in 3 (6.8%), and conduction disorder in 3 (6.8%). The patients had elevated mean serum levels of creatine phosphokinase, aspartate aminotransferases, and gamma glutamyl transferase, as well as hypocalcemia and low levels of total cholesterol and LDL-cholesterol. The patients with altered electrocardiograms had a more elevated age, a lower alcohol consumption, hypopotassemia, and significantly elevated levels of triglycerides, postprandial glucose, sodium and gamma glutamyl transferase than those with normal electrocardiograms. The opposite occurred with fasting glycemia, magnesium, and alanine aminotransferase. CONCLUSION: The electrocardiographic changes found were prolonged QTc interval, change in ventricular repolarization, and left ventricular hypertrophy. Patients with normal and abnormal electrocardiograms had different metabolic and electrolytic changes.

Follow-up study of morphology and cardiac function in rats undergoing induction of supravalvular aortic stenosis

OBJECTIVE: To characterize the follow-up of an experimental model of left ventricular hypertrophy (LVH) induced by supravalvular ascending aortic stenosis in young rats. METHODS: Wistar rats were submitted to thoracotomy and aortic stenosis was created by placing a clip on the ascending aorta (AoS group, n=12). Age-matched control animals underwent a sham operation (C group, n=12). Cardiac function was analysed by echocardiograms performed 6, 12, and 21 weeks after aortic banding. Myocardial morphological features and myocardial hydroxyproline concentration (HOP) were evaluated 2, 6, 12, and 21 weeks after surgery in additional animals. RESULTS: Aortic banding promoted early concentric LVH and a progressive increase in HOP. Under light microscopy, we observed myocyte hypertrophy and wall thickening of the intramural branches of the coronary arteries due to medial hypertrophy. Cardiac function was supranormal after 6 weeks (percentage of fractional shortening - EAo6: 70.3±10.8; C6: 61.3±5.4; p<0.05), and depressed in the last period. Diastolic dysfunction was detected after 12 weeks (ratio of early-to-late filling velocity - EAo12: 4.20±3.25; C12: 1.61±0.16; p<0.05). CONCLUSION: Ascending aortic stenosis promotes concentric LVH with myocardial fibrosis and minimal histological changes. According to the period of evaluation, cardiac function may be improved, normal, or depressed. The model is suitable and useful for studies on pathophysiology and treatment of the different phases of cardiac hypertrophy.

Relevance of Target-Organ Lesions as Predictors of Mortality in Patients with Diabetes Mellitus

Background: Patients with diabetes are in extract higher risk for fatal cardiovascular events. Objective: To evaluate major predictors of mortality in subjects with type 2 diabetes. Methods: A cohort of 323 individuals with type 2 diabetes from several regions of Brazil was followed for a long period. Baseline electrocardiograms, clinical and laboratory data obtained were used to determine hazard ratios (HR) and confidence interval (CI) related to cardiovascular and total mortality. Results: After 9.2 years of follow-up (median), 33 subjects died (17 from cardiovascular causes). Cardiovascular mortality was associated with male gender; smoking; prior myocardial infarction; long QTc interval; left ventricular hypertrophy; and eGFR <60 mL/min. These factors, in addition to obesity, were predictors of total mortality. Cardiovascular mortality was adjusted for age and gender, but remained associated with: smoking (HR = 3.8; 95% CI 1.3-11.8; p = 0.019); prior myocardial infarction (HR = 8.5; 95% CI 1.8-39.9; p = 0.007); eGFR < 60 mL/min (HR = 9.5; 95% CI 2.7-33.7; p = 0.001); long QTc interval (HR = 5.1; 95% CI 1.7-15.2; p = 0.004); and left ventricular hypertrophy (HR = 3.5; 95% CI 1.3-9.7; p = 0.002). Total mortality was associated with obesity (HR = 2.3; 95% CI 1.1-5.1; p = 0.030); smoking (HR = 2.5; 95% CI 1.0-6.1; p = 0.046); prior myocardial infarction (HR = 3.1; 95% CI 1.4-6.1; p = 0.005), and long QTc interval (HR = 3.1; 95% CI 1.4-6.1; p = 0.017). Conclusions: Biomarkers of simple measurement, particularly those related to target-organ lesions, were predictors of mortality in subjects with type 2 diabetes.

Relevance to Home Blood Pressure Monitoring Protocol of Blood Pressure Measurements Taken Before First- Morning Micturition and in the Afternoon

Background: The importance of measuring blood pressure before morning micturition and in the afternoon, while working, is yet to be established in relation to the accuracy of home blood pressure monitoring (HBPM). Objective: To compare two HBPM protocols, considering 24-hour ambulatory blood pressure monitoring (wakefulness ABPM) as gold-standard and measurements taken before morning micturition (BM) and in the afternoon (AM), for the best diagnosis of systemic arterial hypertension (SAH), and their association with prognostic markers. Methods: After undergoing 24-hour wakefulness ABPM, 158 participants (84 women) were randomized for 3- or 5-day HBPM. Two variations of the 3-day protocol were considered: with measurements taken before morning micturition and in the afternoon (BM+AM); and with post-morning-micturition and evening measurements (PM+EM). All patients underwent echocardiography (for left ventricular hypertrophy - LVH) and urinary albumin measurement (for microalbuminuria - MAU). Result: Kappa statistic for the diagnosis of SAH between wakefulness-ABPM and standard 3-day HBPM, 3-day HBPM (BM+AM) and (PM+EM), and 5-day HBPM were 0.660, 0.638, 0.348 and 0.387, respectively. The values of sensitivity of (BM+AM) versus (PM+EM) were 82.6% × 71%, respectively, and of specificity, 84.8% × 74%, respectively. The positive and negative predictive values were 69.1% × 40% and 92.2% × 91.2%, respectively. The comparisons of intraclass correlations for the diagnosis of LVH and MAU between (BM+AM) and (PM+EM) were 0.782 × 0.474 and 0.511 × 0.276, respectively. Conclusions: The 3 day-HBPM protocol including measurements taken before morning micturition and during work in the afternoon showed the best agreement with SAH diagnosis and the best association with prognostic markers.

Ischemia and fibrosis: the risk mechanisms of hypertensive heart disease

Mechanisms underlying risk associated with hypertensive heart disease (HHD) and left ventricular hypertrophy (LVH) are discussed in this report and provide a rationale for understanding this very common and important cause of death from hypertension and its complications. Emphasized are impaired coronary hemodynamics, endothelial dysfunction, and ventricular fibrosis from increased collagen deposition intramurally and perivascularly. Each is exacerbated by aging and, perhaps, also by increased dietary salt intake. These functional and structural changes promote further endothelial dysfunction, altered coronary hemodynamics, and diastolic as well as systolic ventricular contractile function in HHD. The clinical endpoints of HHD include angina pectoris (with or without atherosclerosis of the epicardial coronary arteries), myocardial infarction, cardiac failure, lethal dysrhythmias, and sudden death. The major concept to be derived from these alterations is that not all that is clinically recognized as LVH is true myocytic hypertrophy and structural remodeling. Other major co-morbid changes occur that serve to increase cardiovascular risk including impaired coronary hemodynamics, endothelial dysfunction, and ventricular fibrosis.

Somatic gene therapy for hypertension

Gene therapy for hypertension is needed for the next generation of antihypertensive drugs. Current drugs, although effective, have poor compliance, are expensive and short-lasting (hours or one day). Gene therapy offers a way to produce long-lasting antihypertensive effects (weeks, months or years). We are currently using two strategies: a) antisense oligodeoxynucleotides (AS-ODN) and b) antisense DNA delivered in viral vectors to inhibit genes associated with vasoconstrictive properties. It is not necessary to know all the genes involved in hypertension, since many years of experience with drugs show which genes need to be controlled. AS-ODN are short, single-stranded DNA that can be injected in naked form or in liposomes. AS-ODN, targeted to angiotensin type 1 receptors (AT1-R), angiotensinogen (AGT), angiotensin converting enzyme, and ß1-adrenergic receptors effectively reduce hypertension in rat models (SHR, 2K-1C) and cold-induced hypertension. A single dose is effective up to one month when delivered with liposomes. No side effects or toxic effects have been detected, and repeated injections can be given. For the vector, adeno-associated virus (AAV) is used with a construct to include a CMV promoter, antisense DNA to AGT or AT1-R and a reporter gene. Results in SHR demonstrate reduction and slowing of development of hypertension, with a single dose administration. Left ventricular hypertrophy is also reduced by AAV-AGT-AS treatment. Double transgenic mice (human renin plus human AGT) with high angiotensin II causing high blood pressure, treated with AAV-AT1-R-AS, show a normalization of blood pressure for over six months with a single injection of vector. We conclude that ODNs will probably be developed first because they can be treated like drugs for the treatment of hypertension with long-term effects. Viral vector delivery needs more engineering to be certain of its safety, but one day may be used for a very prolonged control of blood pressure.