Arterial distensibility as a possible compensatory mechanism in chronic aortic insufficiency.

OBJECTIVE: To evaluate elastic properties of conduit arteries in asymptomatic patients who have severe chronic aortic regurgitation. METHODS: Twelve healthy volunteers aged 30+/-1 years (control group) and 14 asymptomatic patients with severe aortic regurgitation aged 29+/-2 years and left ventricular ejection fraction of 0.61+/-0.02 (radioisotope ventriculography) were studied. High-resolution ultrasonography was performed to measure the systolic and diastolic diameters of the common carotid artery. Simultaneous measurement of blood pressure enabled the calculation of arterial compliance and distensibility. RESULTS: No differences were observed between patients with aortic regurgitation and the control group concerning age, sex, body surface, and mean blood pressure. Pulse pressure was significantly higher in the aortic regurgitation group compared with that in the control group (78+/-3 versus 48+/-1mmHg, P<0.01). Arterial compliance and distensibility were significantly greater in the aortic regurgitation group compared with that in the control group (11.0+/-0.8 versus 8.1+/-0.7 10(-10) N-1 m4, P=0.01 e and 39.3+/-2.6 versus 31.1+/-2.0 10(-6) N-1 m2, P=0.02, respectively). CONCLUSION: Patients with chronic aortic regurgitation have increased arterial distensibility. Greater vascular compliance, to lessen the impact of systolic volume ejected into conduit arteries, represents a compensatory mechanism in left ventricular and arterial system coupling.

Ressonância nuclear magnética no diagnóstico de pseudoaneurisma de ventrículo esquerdo: antigo problema, nova opção / Nuclear magnetic resonance imaging in the diagnosis of left ventricular pseudoaneurysm: an old problem, a new option

Paciente feminina, 67 anos, internada por infarto agudo do miocárdio de parede lateral, com edema agudo de pulmão e evolução para choque cardiogênico nas primeiras horas. Ecocardiograma transesofágico e ressonância magnética confirmaram o diagnóstico de pseudoaneurisma de ventrículo esquedo. A paciente foi submentida a tratamento cirúrgico com sucesso.

[Nuclear magnetic resonance imaging in the diagnosis of left ventricular pseudoaneurysm. An old problem, a new option]. / Ressonância nuclear magnética no diagnóstico de pseudoaneurisma de ventrículo esquerdo. Antigo problema, nova opção.

We describe the case of a 61 year-old female patient admitted to the hospital with acute lateral myocardial infarction, in pulmonary edema, who evolved to cardiogenic shock in the first hours. Transesophageal echodoppler-cardiogram and nuclear magnetic resonance imaging showed the diagnosis of a left ventricular pseudoaneurysm. Surgical repair was successfully undertaken.

[Mitral subvalvular aneurysm of the left ventricle]. / Aneurisma subvalvar mitral de ventrículo esquerdo.

A 21-year-old white man presented with cardiogenic shock and refractory pulmonary congestion. At the transthoracic echocardiogram a subvalvar left ventricular aneurysm of the inferior wall with severe mitral regurgitation was observed. The outcome was favorable after surgical correction of the mitral regurgitation and of the subvalvar aneurysm. We emphasize that, whenever possible, valvar repair is better than mitral replacement, since annulus tissue fragility causes suturing of the mitral prosthesis to be difficult.

[Intensive Care Unit stay. Variables that affect emotional reactions]. / Internação em UTI. Variáveis que interferem na resposta emocional.

PURPOSE: To evaluate the anxiety and depression levels during five days of stay in a Clinical Cardiological Intensive Care Unit (ICU) and verify the relation to different variables. METHODS: Forty seven patients were submitted to IDATE scale for anxiety and an avaliation for depression. The scores were compared to medical diagnoses, age, local of stay before the ICU, number of hospitalizations. RESULTS: Anxiety and depression scores decrease significant from first to fifth day of ICU stay. No significant correlation was found between age, number of hospitalizations, medical diagnoses and the anxiety and depression scores. Patients admitted from the emergency unit presented a correlation between anxiety and depression scores. CONCLUSION: Anxiety and depression decrease during the five days of ICU stay. Emotional reactions are not influenced by medical diagnoses, age and number of hospitalizations. The emergency unit stay affects emotionally the patient in the first days of ICU admission.

Carotid arterial compliance in patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy.

Conduit artery distensibility affects the pulsatile component of afterload and may contribute to impaired left ventricular function in patients with congestive heart failure (CHF). The objectives of this study were to (1) determine whether arterial distensibility is reduced in patients with CHF, and (2) determine whether decreased arterial compliance is related to an abnormality in vascular wall structure (i.e., wall thickness or excessive levels of circulating neurohumoral vasoconstrictors, or both). The study participants included 40 patients with CHF secondary to idiopathic dilated cardiomyopathy and 33 age-matched healthy volunteers. High-resolution ultrasonography was performed to directly visualize the common carotid artery and measure its diameter and wall thickness. Its elastic properties were determined by relating changes in arterial diameter to changes in pressure generated with each heart beat. Carotid artery distensibility was less (14.1 +/- 1.1 vs 25.3 +/- 1.6 10(-6).N-1.m2, p < 0.001) and Young's modulus of elasticity was greater (3.99 +/- 0.51 vs 2.29 +/- 0.23 10(5).N.m-2, p < 0.005) in patients with CHF than in normal subjects. Also, carotid artery wall thickness was increased in patients with CHF. When the entire population was considered, age, wall thickness, and plasma norepinephrine and aldosterone concentrations correlated inversely with distensibility, whereas age and plasma norepinephrine concentration correlated directly with elasticity. Among normal subjects, only age correlated inversely with distensibility; among patients with CHF, only plasma norepinephrine concentration correlated with elasticity. It is concluded that carotid artery distensibility is reduced in patients with CHF.(ABSTRACT TRUNCATED AT 250 WORDS)

[Acute liver failure secondary to cardiogenic shock in patients with congestive heart failure]. / Falência hepática aguda secundária a choque cardiogênico em portadores de insuficiência cardíaca congestiva.

Fulminant hepatic failure is a complication of severe cardiocirculatory failure, with high morbidity and mortality, and is frequently misdiagnosed as fulminant viral hepatitis. We report three cases of patients with chronic severe heart failure who developed cardiogenic shock complicated by elevation of aminotransferase levels above 1,000 soon after the most severe episode of hypotension. All the three patients presented regression of hepatic enzymes 72h after admission. Two patients developed hepatic encephalopathy and renal failure. One underwent the implantation of an artificial left ventricle, followed by orthotopic heart transplantation. One died of systemic multiple organ failure, after he had showed improvement on his hepatic profile, and one was sent to the ward, after 15 days with marked improvement on his clinical status and no signs of hepatic disease.

[Thiocyanate toxicity arising from prolonged use of sodium nitroprusside in severe heart failure]. / Toxicidade pelo tiocianato decorrente do uso prolongado de nitroprussiato de sódio na insuficiência cardíaca grave.

PURPOSE: To evaluate the toxicity of thiocyanate induced by the infusion of sodium nitroprusside in patients with severe congestive failure. METHODS: We studied 23 patients with congestive heart failure, in class IV (NYHA) under continuous infusion of sodium nitroprusside with doses varying between 0.5 and 5.5 micrograms/kg/min. Clinical evaluation, thiocyanate serum dosage and laboratorial evaluation of renal, hepatic and pulmonary functions were done. RESULTS: Seventeen patients (74%) presented toxic levels of thiocyanate (over 10 micrograms/ml), with the average of 29.9 +/- 4.4 micrograms/ml. Only renal function was related to the presence of intoxication. Clinical evaluation was not accurate to diagnose the thiocyanate toxicity in the patients. CONCLUSION: Sodium nitroprusside is potentially toxic, especially when the renal function is abnormal. Thiocyanate dosage is useful in diagnosing nitroprusside induced toxicity and then it contributes to an adequate treatment and prevention of clinical toxicity.

Choque cardiogênico / Shock cardiogenic

O choque cardiogênico caracteriza-se quando uma severa disfunçäo miocárdica provoca hipoperfusäo tecidual e falência orgânica. Os critérios exatos para a presença de choque cardiogênico variam muito na literatura. Além disso é extremamente importante comparar o grau da disfunçäo miocárdica quando se analisam os resultados de diferentes procedimentos. Em 1973, importante estudo multicêntrico estabeleceu os seguintes critérios para a definiçäo de choque cardiogênico: - pressäo arterial sistólica < 80 mmHg (intra-arterial); - débito urinário < 20 ml/h ou confusäo mental; - pressäo de enchimento ventricular > 12 mmHg; - pressäo venosa central > 10 cm H20. Esta definiçäo tem grande utilidade clínica pois inclui a classificaçäo de Kilip para o infarto agudo do miocárdio. Além disso, incorpora os três principais componentes do choque cardiogênico: 1) comprometimento da funçäo ventricular; 2) evidência de falência orgânica como resultado do decréscimo da perfusäo tecidual; e 3) exclusäo de hipovolemia e outras causas do choque. Uma vez que esta definiçäo já foi largamente aplicada com sucesso em estudos prospectivos, pode ser considerada padräo para estudos clínicos futuros.

Relationship of arterial compliance to baroreflex function in hypertensive patients.

The objectives of this study were to determine whether carotid arterial compliance is reduced in patients with hypertension and to assess whether reduced arterial compliance is related to abnormal arterial baroreflex function. Accordingly, concurrent measurements of carotid arterial diameter (via computerized high resolution B-mode ultrasonography) and blood pressure were made to determine carotid arterial compliance in 23 normotensive and 16 age-matched hypertensive patients. In addition, arterial baroreflex function was assessed in 12 of the normal subjects and nine of the hypertensive patients by measuring the infusions of nitroprusside and phenylephrine. Compared with the normotensive subjects, the patients with hypertension had reduced compliance (5.9 +/- 0.7 vs. 16.6 +/- 1.8 10(-7) m2/kPa, mean +/- SE, P < 0.001). The baroreflex slope relating the change in R-R interval to the change in systolic blood pressure during the drug infusions was less in the hypertensive than normotensive subjects (12.3 +/- 2 vs. 18.9 +/- 2 ms/mmHg, P < 0.05). Consequently, when both normotensive and hypertensive subjects were considered, there was a significant correlation between the baroreflex slope and compliance (r = 0.53, P < 0.05). However, there was no correlation between the baroreflex slope and compliance within either the normotensive group (r = 0.04, P = NS) or the hypertensive group (r = 0.43, P = NS) when analyzed separately. There was a significant correlation between age and compliance (r = -0.48, P < 0.01) but not between age and baroreflex function.(ABSTRACT TRUNCATED AT 250 WORDS)

[Hemodynamic variable analysis in patients with systemic arterial hypertension undergoing physical exercise]. / Análise das variáveis hemodinâmicas em pacientes com hipertensão arterial sistêmica submetidos ao exercício físico.

PURPOSE: To verify the exercise-induced hemodynamic changes in moderate hypertensive patients. METHODS: Twenty nine patients were studied and they were submitted to cycloergometer supine exercise (50w and 100w) during cardiac catheterization. The hemodynamic variables were measured: cardiac index (CI), stroke volume (SV), systemic arterial resistance (SAR), pulmonary arterial resistance (PAR), wedge pressure (WP), right atrial pressure (RA), systolic arterial pressure (SP), diastolic arterial pressure (DP), mean arterial pressure (MP) and heart rate (HR). To evaluate the cardiac function, the patients were divided in two groups: GI with CI > 2.5 ml/min/m2 and GII CI < 2.5 ml/min/m2. RESULTS: During exercise, patients from GI and GII were similar-according to MAP, RA, WP, and HR. On the other hand, GI and GII exhibited different (#) behavior regarding SV, PAR and SAR. During the three exercise conditions, rest (R), 50w and 100w it was observed: a) PAR-R = 50 = 100 (GI); b) MP, PAR, WP, SV, SAR-R #50 #100 (GI); c) HR, PAR and SAR-R #50 #100 (GII). There was no correlation between the cardiac function (CI, SV) and the circulatory adjustment (PAR and SAR) or the pressure curve (SP, DP, MP) and HR. CONCLUSION: The results suggest that the cardiac function of GI patients depends, mainly, on the inotropism, while in GII patients it depends on the decrease of the afterload (PAR and SAR). Those changes may appear even in the late exercise stage (100w), with a bias to attain the GI levels. Those observations suggest functional changes in vasomotor tone of GII patients.

[The effect of intravenous furosemide on the hemodynamic parameters and colloid osmotic pressure in patients with pulmonary edema]. / Efeito da furosemida endovenosa sobre os parâmetros hemodinãmicos e na pressão coloidosmótica em pacientes com congestão pulmonar.

PURPOSE: To evaluate the effects of intravenous furosemide over hemodynamics variables and colloid osmotic pressure in patients with pulmonary edema. METHODS: Eight patients with pulmonary edema, mean age of 58.3 +/- 7.5 years, 6 men, were evaluated. Hemodynamic monitoring was performed by Swan-Ganz catheter in pulmonary artery to obtain RAP and PAWP, in mmHg, and HR, in bpm. Cardiac output (CO) was obtained by thermodilution method. Cardiac index (CI) in L/min/m2, and systolic index, in ml, arose from variables above. Mean arterial pressure (MAP), in mmHg, was obtained through catheterization of radial artery. patients were treated with 20 mg of intravenous furosemide, and hemodynamic variables were measured before and after 5, 15, 30, 60 and 120 minutes. COP was measured in Weil oncometer (IL 196) at same intervals. RESULTS: A significant reduction of RAP (p = 0.002) and PAWP (p < 0.0001), HR (p = 0.02), COP (p < 0.0001) and gradient between PAWP-COP (p < 0.0001) were observed. RAP and PAWP reduction was greater in the first five minutes and, otherwise, COP reduction was gradual in 120 min. PAWP-COP gradient initially positive, stayed negative during all study. MAP, CI, SI and SVR did not show statistical differences. CONCLUSION: Furosemide administration reduced RAP, PAWP, HR, COP and PAWP-COP gradient, probably by a redistribution of fluid excess in the interstitial to intravascular space, through changes in driving fluid forces, with predominance in colloid osmotic pressure, which reverse fluid from intravascular to interstitial observed in pulmonary edema.

[Circulatory assist device in counterpulsation]. / Dispositivo de assistencia circulatoria em contrapulsacao.

PURPOSE: To test a circulatory assist device (CAD) developed in the University of São Paulo. Heart Institute, Bioengineering Division. It is a valveless chamber working through the counterpulsation principle, aiming at assistance to temporary the left ventricle. PATIENTS AND METHODS: The CAD consists of a rigid polycarbonate shell, which houses in its interior a polyurethane bag with a maximum volume of 110 cm3, driven alternately by pressure and vacuum from an external electropneumatic device synchronized with the ECG. The device worked for 300 hours in a test bench simulating the cardiovascular system in order to verify its resistance to wear and fatigue. The CAD was implanted near the aortic root of five dogs, in whom cardiac failure was induced through the use of propranolol and plasma expanders. The CAD was driven for five periods of 2 minutes separated by pauses of equal duration. The hemodynamic parameters were measured during the mentioned periods. RESULTS: "In vitro" testing resulted in no wear or fatigue. No leakage was observed. In the "in vivo" testing the averages obtained during the on and off periods of the device showed for the on periods; a) lowering of the systolic pressures of both the aorta (17.5%) and the left ventricle (LV) 15.1%), lowering of the final diastolic pressure of the LV (15.4%) and lowering of the diastolic pressure of the aorta (27.4%); b) increase in cardiac output (45.5%); c) increase of the endocardial viability ratio by 37.5%. CONCLUSION: The tested device represents a therapeutic option in cases of acute left ventricle failure, since with it an improved cardiac performance was measured and an increased coronary perfusion can be presumed.

Difference between the response of the pulmonary and systemic circulation during exercise in congestive heart failure.

Thirty nine patients with cardiomyopathy were evaluated by a hemodynamic study at rest and during isotonic exercise. These patients were divided into two groups on the basis of their left ventricular ejection fraction (LVEF): A, control group (LVEF greater than 40%, N = 19); B, severe congestive heart failure group (LVEF less than or equal to 40%, N = 20). Patients in group A showed adequate cardiovascular responses to exercise, i.e. increased cardiac index (80%) and stroke volume index (17%), decreased systemic vascular resistance (36.8%) but no significant change in pulmonary arteriolar resistance values. In contrast, patients in group B showed a slight and heart rate-dependent increase in cardiac index (38.5%), no improvement of stroke volume index (-3.4%), decreased systemic vascular resistance (21.6%) and increased pulmonary arteriolar resistance (41.2%) with exercise. This group also showed a significant increase in right atrial pressure that might reflect a decrease in right ventricular performance secondary to an abnormal pulmonary vascular response during exercise.