Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of mechanical ventilation with and without positive end-expiratory pressure (PEEP) on hemodynamic performance and blood-gas exchange were studied in ten patients following open-heart surgery. Ventilation at constant tidal volume (15 ml/kg body weight) with 10 cm H2O PEEP following aortic valve replacement (AVR) IN FIVE PATIENTs without pulmonary vascular disease was associated with the following significant changes: a rise in arterial Po2, a fall in the alveolar-arterial Po2 gradient when Fio2 = 1.0, decreases in calculated Qs/Qt and cardiac index. Using a similar pattern of ventilation following mitral valve replacement (MVR) in patients with elevated pulmonary vascular resistance, we found a significant decrease in cardiac index (but less than in the AVR group), a significant elevation of calculated physiologic deadspace (Vd/Vt) and no change in Qs/Qt. An hour after removal of PEEP, intravascular pressures, blood flow and blood-gas exchange values of all patients with AVR had returned to control levels; patients with MVR had persistently significantly low cardiac indices, while Vd/Vt returned to pre-PEEP values. These findings suggest that evaluation of responses to different ventilation patterns must take into account pre-existing V/Q abnormalities secondary to pulmonary vascular disease, particularly when these are secondary to chronic congestive heart failure. Following AVR, Qs/Qt changed in the same direction as cardiac index (CI) irrespective of ventilatory pattern: CI decreased and rose as CI increased. The authors conclude that with increasing severity of pulmonary vascular disease, changes in airway pressure will have an unpredictable effect on cardiac index unless the level of myocardial competence is taken into account. In the presence of ventricular failure, changes in pleural (and therefore transmural) pressures will be minimal compared with the high filling pressures and exert no influence on stroke volume. Although pulmonary venous hypertension was more pronounded in the MVR than in the AVR group, there was no significant difference between the postoperative values for Qs/Qt (Fio2 = 1.0), a condition probably fostered by marked differences in pre-existing V/Q.
 ...
PMID:The effect of pre-existing pulmonary vascular disease on the response to mechanical ventilation with PEEP following open-heart surgery. 23 11

Measurements of mean left ventricular (LV) and regional myocardial blood flow rates were made at rest in 161 patients with 133Xe and a multiplecrystal scintillation camera. Myocardial perfusion rates were correlated with assessments of the degree of coronary artery disease made from the arteriograms obtained during the same studies. In patients with normal coronary arteries without heart failure, the presence of hypertension, aortic stenosis, or aortic insufficiency was not associated with changes in mean LV perfusion from the control value of 61+/-7 ml/100 g-min. However, mean LV perfusion was significantly reduced in patients with normal coronary arteries who had cariomyopathy and impaired ventricular performance. Mean LV perfusion was not significantly different from control values in patients with "mild" coronary artery disease (less than 50% obstruction) or in patients with significant isolated disease (greater than 50% obstruction) of the left anterior descending (lad) artery. Significant reductions in mean LV perfusion were found in patients with greater than 50% obstruction of two coronary arteries (LAD + right or LAD + circumflex) and in patients with triple-vessel disease. The average perfusion rate for regions distal to LAD obstructions in patients with isolated LAD disease was not lower than the LAD perfusion in control patients, but was significantly reduced in patients with LAD + right coronary artery disease (43+/-14 ml/100 g-min). In the latter group average perfusion distal to the LAD lesion was significantly lower than the average regional perfusion rate for the remainder of the LV. However, the mean blood flow rate for the remainder of the LV was also significantly lower than control values despite the lack of significant circumflex disease. The data demonstrate that the presence of radiographically "mild" or significant isolated LAD coronary disease is not associated with reductions in mean LV perfusion at rest, but that mean LV perfusion is reduced in the presence of significant disease of two or three coronary artieries. None of the patients experienced angina during the resting studies and most had clinical evidence of ventricular failure. The observation of depressed LV perfusion in this group, as in the patients with cardiomyopathy, raises the possibility that a lowered resting blood supply may be adequate for a reduced level of performance of a diseased ventricle. The lack of selective reductions of regional perfusion at rest in the majority of the patients with LAD lesions suggests that regional myocardial blood flow must be measured during an intervention which increases myocardial oxygen consumption in order to assess the physiological significance of lesions which are observed at coronary arteriography.
 ...
PMID:The relationship between regional myocardial perfusion at rest and arteriographic lesions in patients with coronary atherosclerosis. 120 79

A 42-year-old patient with acute left-ventricular failure is described in whom pheochromocytoma was diagnosed only after prolonged and fruitless efforts. Pheochromocytoma may present without the typical features of paroxysmal or sustained hypertension, headache, increased sweating, and palpitations. Therefore, in cases of acute left-sided cardiac failure of primarily undetermined origin, pheochromocytoma should be considered in differential diagnosis.
 ...
PMID:[Acute left heart insufficiency: possible leading symptom of a pheochromocytoma]. 157 67

We present a case in which a patient took an overdose of captopril (Capoten) and alprazolam (Xanax) in a suicide attempt. The patient presented with hypotension (systolic blood pressure of 80 mm Hg) and drowsiness. The hypotension initially responded to administration of intravenous fluids and dopamine; however, it recurred twice at 18.5 and 24.5 hours after ingestion. These episodes again responded to administration of fluids and dopamine. A plasma captopril level of 27,391.1 nmol/L (5982 ng/mL) was documented, as well as a depressed level of angiotensin converting enzyme. Captopril is an angiotensin converting enzyme inhibitor used in the management of hypertension and ventricular failure; to our knowledge, this is the first case of an acute captopril overdose reported in the English-language literature. The role of captopril in inducing hypotension is discussed herein.
 ...
PMID:Captopril overdose resulting in hypotension. 328 10

In man, electrocardiographic changes typical of transient myocardial ischemic episodes can be accompanied by increases in arterial pressure and heart rate or, at the opposite side of the spectrum, by decreases in arterial pressure and heart rate. It has been clearly proved that all of these changes can occur independently of the perception of pain. Transient ischemic episodes associated with hypotension and bradycardia or hypotension without the tachycardia that could be expected from a baroreceptive mechanism, are likely to reflect a depressor reflex mediated by cardiac vagal afferent fibers. It is a clinical and experimental working hypothesis that these depressor reflexes would characterise more severe episodes of ischemia: in clinics, those accompanied by signs of acute ventricular failure; in the laboratory, those induced by "global" ischemia. On the other hand, ischemic episodes associated with hypertension and tachycardia, usually thought to depend on a pain mechanism, are likely to reflect a pressor reflex mediated by cardiac sympathetic afferent fibers. It is our hypothesis that these pressor reflexes from the heart are the most frequent companions of less severe ischemic episodes, whether or not signalled by anginal pain. In the laboratory, a pressor reflex can be constantly obtained with a limited "regional" ischemia. These neural mechanisms, that should be analyzed independently of any teleologic reasoning, may be of paramount importance not only in determining the hemodynamic profile accompanying ischemic episodes, but in inducing those local changes in visceral neural activity that an increasing evidence indicates as crucial factors in arrhythmias and coronary death.
 ...
PMID:Circulatory markers of nervous activation during myocardial ischemia. 375 96

We studied the indications for use, time to onset of effect, approximate effective concentration and therapeutic success of commercially prepared intravenous nitroglycerin (NTG) in 50 patients undergoing cardiopulmonary bypass (CPB) surgery. Nitroglycerin was used to treat systemic or pulmonary hypertension, myocardial ischaemia and ventricular failure. Twenty-one patients had more than one indication for NTG use. Nineteen of 22 patients with pulmonary hypertension, 12 of 13 patients with ischaemic changes, and 13 of 15 patients with ventricular failure improved during intravenous NTG administration. Hypertension during CPB was ameliorated in only six of ten instances. The time to onset of effect ranged from 4.1 +/- 0.8 to 7.8 +/- 2.8 minutes and the mean approximate effective NTG concentration varied from 1.7 +/- 0.3 to 2.9 +/- 0.7 micrograms . kg-1.min-1 (doses only approximate due to our use of an infusion system which absorbs NTG). Complications from intravenous NTG administration were not seen. We conclude that this NTG preparation facilitates treatment of prebypass hypertension, pulmonary hypertension, myocardial ischaemia and ventricular failure but is less effective for the treatment of hypertension during CPB.
 ...
PMID:A profile of intravenous nitroglycerin use in cardiopulmonary bypass surgery. 640 4

The so-called safe course of acute myocardial infarction was shown to be associated with reduced left ventricular stroke output, changed phasic pattern of the systole, and peripheral arterial constriction. In infarction-related acute left-ventricular failure, a clear dissociation can be seen between the pumping function of the right and left ventricles. These changes are further aggravated by increased circulating blood volume and pulmonary blood quantity, and lowered arterial and venous flow rate. Paravascular edema adds to generalized vasoconstriction. Hypertension in the pulmonary artery network implies additional effort for right ventricular myocardium and thus prevents blood overflow to lesser circulation veins and left compartments of the heart.
 ...
PMID:[Comparative hemodynamic aspects in acute myocardial infarctions with various clinical patterns]. 662 Aug 7

To determine whether nitroglycerin is just as effective as nifedipine in lowering the blood pressure in excessive hypertension and hypertensive crisis, two groups of 20 patients received in random sequence either 1.2 mg of nitroglycerin sublingually or a 10 mg nifedipine capsule, which was chewed and swallowed. The blood pressure fell after 5 min in the nitroglycerin group from 211/122 mm Hg to 171/95 mm Hg and after nifedipine from 210/118 to 185/102 mm Hg. The greater effect of nitroglycerin results from faster absorption through the oral mucosa than through the small intestinal mucosa where nifedipine is primarily absorbed. After 15 to 20 min a satisfactory reduction in blood pressure was reached in both groups: 157/91 and 158/92 mm Hg, respectively. After 30 min the heart rate in the nitroglycerin group had decreased from 83 to 80/min, but in the nifedipine group it had increased from 84 to 90/min. The reduction in blood pressure persisted up to 6 h. No significant difference in side-effects was determined. Since a hypertensive crisis is usually accompanied by left-ventricular failure, pulmonary edema or angina pectoris and infarction, and nitroglycerin has been definitively shown to positively influence these conditions, preference should be given to nitroglycerin in the treatment of hypertensive crisis.
 ...
PMID:[Nitroglycerin in comparison with nifedipine in patients with hypertensive crisis]. 847 Apr 17

This study sought to determine the impact of female gender on clinical outcome in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) due to predominant ventricular failure undergoing percutaneous coronary intervention (PCI). We analyzed gender-related differences in procedural, angiographic, and clinical outcomes in 208 consecutive patients with AMI complicated by CS. Out of 208 patients with CS, 65 were women and 143 men. Women were older than men (74 +/- 10 years vs. 66 +/- 12 years; P < 0.001) and had a greater incidence of a history of hypertension (43% vs. 29%; P = 0.041). The 6-month mortality rate was 42% in women and 31% in men (P = 0.157). There were no differences between groups in reinfarction rate and target vessel revascularization rate. Multivariate analysis showed age as the only variable independently related to the 6-month mortality, while female gender was not related to the risk of death. The benefit of early PCI is similar in women and men, and any potential referral bias in the use of PCI based on gender differences should be avoided.
 ...
PMID:Does gender affect the clinical outcome of patients with acute myocardial infarction complicated by cardiogenic shock who undergo percutaneous coronary intervention? 1289 99

An infant, 2 months old, underwent cardiac surgery because of congenital heart defects and pulmonary hypertension. Surgery was performed in hypothermia and cardiac standstill. On the second day after surgery the infant had to be resuscitated due to a combination of acute left-ventricular failure, pulmonary vascular hypertension and a slight right-to-left-shunt. A breakthrough in the treatment was achieved by using levosimendan to improve left-ventricular function and to decrease vascular resistance.
 ...
PMID:Treatment of acute heart failure in an infant after cardiac surgery using levosimendan. 1520 Oct 12


1 2 Next >>