Hemodynamic and coronary effects of intravenous labetalol in coronary artery disease.

Labetalol, an alpha and beta receptor blocking agent, was evaluated in 11 patients with documented coronary artery disease and stable angina. The mean dose of labetalol was 1.5 (range 1 to 2) mg/kg. Cardiovascular effects began within 1 minute after injection and were maximal within 10 minutes. Mean arterial pressure decreased from 105 +/- 13 to 81 +/- 10 mm Hg (p less than 0.0001), heart rate from 70 +/- 10 to 66 +/- 7 beats/min (p less than 0.05) and the pressure-rate product from 10,322 +/- 2,344 to 7,171 +/- 1,650 (p less than 0.001). Cardiac output and pulmonary wedge pressure did not change significantly. Mean pulmonary arterial pressure decreased from 20 +/- 3 to 16 +/- 2 mm Hg (p less than 0.005). Systemic and pulmonary resistances also decreased significantly (p less than 0.0001 and p less than 0.01, respectively). Coronary sinus flow increased from 107 +/- 26 to 118 +/- 25 ml/min (p less than 0.01) and coronary vascular resistance decreased from 1.0 +/- 0.2 to 0.77 +/- 0.1 mm Hg/ml per min (p less than 0.001). Labetalol may be a useful adjunct in the treatment of angina not only because it diminishes myocardial oxygen requirements but also because it improves coronary hemodynamics. Thus, labetalol appears to have some advantage compared with the usual beta blocking agents with their potentially detrimental effects on coronary hemodynamics.

Combined hemodynamic effects of dobutamine and IV nitroglycerin in congestive heart failure.

The combined and separate hemodynamic effects of dobutamine and IV nitroglycerin were compared in 12 patients with chronic congestive heart failure (nine with ischemic heart disease, two with idiopathic congestive cardiomyopathy, and one with valvular heart disease). Dobutamine (7.1 micrograms/kg/min) increased cardiac index from 2.4 +/- 0.4 to 3.4 +/- 0.9 L/min/m2 (P < 0.001) and decreased pulmonary wedge pressure from 28 +/- 5 to 16 +/- 4 mm Hg (P < 0.001) while nitroglycerin (127 micrograms/min) alone increased cardia index to 2.8 L/min/m2 (P < 0.001) and decreased wedge pressure to 14.3 mm Hg (P < 0.001). With both drugs, cardiac index increased to 3.5 +/- 0.6 L/min/m2; (NS compared to dobutamine alone) wedge pressure decreased to 11 +/- 4L/min/m2 (P < 0.05 compared to dobutamine alone). Those beneficial hemodynamic effects occurred without a significant change in the double product of heart rate and blood pressure, and were associated with an improvement in the transmyocardial gradient. Thus, the greatly enhanced ventricular performance with dobutamine + nitroglycerin was associated with a better relationship between myocardial oxygen demand and supply.

Transient left ventricular pulsus alternans in severe aortic valve disease.

A 56-year-old man presented with severe aortic valve disease. Pulsus alternans was recorded in the left ventricle, apparently provoked by catheter placement through a stenotic aortic valve. This case illustrates that studies on left ventricular performance in severe aortic stenosis should be done with a transseptal catheter.

Spontaneous resolution of severe right ventricular dysfunction in right ventricular infarction: documentation by radionuclide studies.

A case of inferior myocardial infarction complicated by severe arrhythmias and right heart failure is presented. Radionuclide studies performed near the acute phase and one month later illustrate the reversibility of right heart dysfunction caused by infarction. Signs of right ventricular involvement in acute inferior myocardial infarction are noted in about 40% of cardiac blood-pool studies: right ventricular dilatation with a significantly decreased ejection fraction, and ventricular wall motion abnormalities. Follow-up studies in the recovery period show good recovery of right ventricular function.

Evaluation of the alpha and beta blocking effects of intravenous labetalol on left ventricular function in coronary artery disease.

Intravenous labetalol was evaluated in 10 patients with stable angina without heart failure. Mean dose was 1.75 mg/kg (range 1.5-2 mg/kg). Measurements were taken within one minute after the injection, and at 1, 5 and 15 minutes thereafter. Labetalol significantly decreased blood pressure and increased heart rate. Peak aortic flow velocity increased only significantly at 1 minute; dP/dt+ max. was significantly decreased during all the measurements. Left ventricular end diastolic pressure did not change. Thus in patients without failure left ventricular function remained stable despite the negative inotropic effects of labetalol.

Perioperative coronary spasm and right ventricular ischemia.

Perioperative coronary spasm after coronary bypass surgery is increasingly recognized as a possible cause of circulatory collapse. Most of the reported cases involved the right coronary artery (RCA). A case where transient right coronary spasm provoked right ventricular ischemia and collapse is described.

Chronic aortic regurgitation: a demonstration of the effect of bradycardia on left ventricular function.

A 50-year-old man with previously asymptomatic aortic regurgitation presented with clinical, echocardiographic and hemodynamic deterioration secondary to bradycardia. The effects of prolonged diastolic time were demonstrated in the catheterization laboratory; immediate improvement in left ventricular end diastolic and aortic diastolic pressures were noted after the insertion of a temporary pacemaker at a heart rate of 70 beats/min. In patients with aortic regurgitation and unexpected deterioration, bradycardia should be considered.

Late coronary aneurysm formation following coronary angioplasty.

In a 38-year-old man with recurrent chest pain 14 months following percutaneous transluminal coronary angioplasty (PTCA) of the left anterior descending coronary artery, two aneurysms were noted at previous PTCA sites without evidence of restenosis. Although the precise mechanism of formation of these aneurysms is not known, it is possible that medial dissection and weakening of the artery provoked aneurysm formation.

Long-term survival and functional status in the elderly after cardiac surgery.

BACKGROUND: Hospital mortality and morbidity of cardiac surgery have been well described in the elderly, but there is a paucity of data regarding long-term functional status. OBJECTIVE: To evaluate long-term survival and functional status of patients aged 70 years or older after cardiac surgery. DESIGN: Retrospective observational study. SETTING: University-affiliated tertiary care hospital. PATIENTS: Three hundred and twenty-nine consecutive patients aged 70 or older who had undergone cardiac surgery from January 1990 to December 1993. INTERVENTIONS: Besides postoperative mortality and morbidity, data regarding long-term survival and functional status and preoperative variables affecting these outcomes were analyzed. MAIN RESULTS: Mean age at surgery was 73.9 +/- 2.9 years, and 70.2% of the procedures were performed on an urgent basis. Postoperative mortality was 9.4%. Five-year Kaplan-Meier survival in postoperative survivors was 85.9% and is comparable with the survival of the general sex- and age-matched Quebec population. Preoperative variables affecting long-term survival were atrial fibrillation (RR 3.8; 95% CI 1.4 to 10.0), smoking status on admission (RR 3.6; CI 1.6 to 8.1), peripheral vascular disease (RR 2.9; CI 1.4 to 6.2) and low creatinine clearance (RR 1.4; CI 1.1 to 1.7). Functional status evaluated by the Karnofsky score showed a successful functional outcome in 84.6% of patients at follow-up (mean 2.6 +/- 1.1 years). Preoperative variables unfavourably influencing a successful functional outcome were hypertension (OR 0.34; CI 0.15 to 0.76), cerebrovascular disease (OR 0.35; CI 0.15 to 0.87) and low creatinine clearance (OR 0.73; CI 0.55 to 0.96). CONCLUSIONS: Despite severe cardiovascular and often urgent conditions, sustained functional improvement and good long term survival can be objectively documented in most elderly patients after cardiac surgery.

The role of coronary angioplasty in patients with associated noncardiac medical and surgical conditions.

Percutaneous transluminal coronary angioplasty was performed in 22 patients with associated significant medical or surgical conditions. It was successful in 22 patients. Two had procedure-related complications: one femoral hematoma and one small myocardial infarction. The patients were divided into a 'medical' group (12 patients) and a 'surgical' group (10 patients). In the medical group, mean coronary artery stenosis decreased from 87 +/- 5% to 20 +/- 13% and mean coronary artery stenosis decreased from 57 +/- 2% to 16 +/- 7%. In the surgical group coronary artery stenosis decreased from 83 +/- 9% to 18 +/- 9% and the gradient from 49 +/- 16 to 16 +/- 6 mmHg. Percutaneous transluminal coronary angioplasty allowed the safe management of underlying conditions in all patients so that medical treatment could be continued and noncardiac surgery performed.

[Epidural stimulation in the treatment of refractory angina]. / La stimulation épidurale dans le traitement de l'angine réfractaire.

Twelve patients with refractory angina pectoris previously treated with angioplasty or coronary bypass and under optimal medical therapy were treated with spinal cord electrical stimulation (SCES) at the C7 to D2 level since 1988. Six patients had a significant improvement of symptoms confirmed by a reduced incidence of chest pain and decreased used of nitroglycerin. Three patients required removal of electrode (heart transplantation, inadequate comprehension and foreign body reaction). These patients did however benefit from the effect of SCES for sometimes. Three patients died. The SCES may improve the quality of life by reducing the incidence of chest pain in patients previously uncontrolled with maximal medical and surgical therapy.

Cardiac conduction abnormalities and Stokes-Adams attacks in myotonic dystrophy.

Myotonic dystrophy is a well known cause of cardiomyopathy. While various cardiac conduction abnormalities have been described in patients with myotonic dystrophy, so far only sporadic cases of Stokes-Adams attacks have been reported. Of 27 patients with this disease various conduction disturbances were detected in 17 (63%), 5 of whom presented with Stokes-Adams attacks and were found to have intracardiac conduction defects. The prognosis in four of the five patients was greatly improved with permanent pacemaker implantation.

Effects of angiographic contrast media on colloid oncotic pressure.

Angiographic contrast media are known to induce alterations in cardiovascular dynamics which may result in acute pulmonary edema. The risk of pulmonary edema was previously shown to be negatively correlated to the level of colloid oncotic pressure (COP). It was also shown that the gradient between COP and left ventricular end-diastolic pressure (LVEDP) represents a better predictor of pulmonary edema than does LVEDP alone. The present report evaluates the effects of a bolus injection of contrast media on those pressures, as predisposing factors for pulmonary edema. Our data are based on 15 unselected patients admitted for coronary angiography. The plasma volume increased by 16.5% (2,903 to 3,384 ml.) at two minutes after injection of a 50 c.c. bolus of meglumine diatrizoate (Renographin 76%) and had returned towards normal at 30 minutes. In parallel the COP decreased from 23.4 +/- 2.4 to 19.6 +/- 2.3 mm. Hg (p < 0.001) to return the 22.7 +/- 2.6. The COP-LVEDP gradient decreased by 8.7 mm. Hg (8.4 to -0.3, P < 0.001). Such a gradient was well within the danger zone of pulmonary edema. These findings further clarify the mechanisms of pulmonary edema induced by contrast media.

Streptokinase thrombolysis of a chronically thrombosed mitral prosthetic valve.

Thrombus obstruction of a prosthetic heart valve is usually treated surgically. We report a well-documented case of an obstructed mitral prosthetic valve where fibrinolytic treatment was successful. Furthermore the thrombus formation probably had occurred 6 months earlier. Thus fibrinolysis appears to be a safe alternative to surgery although late occurrence of thrombosis may be possible.

The role of intravenous streptokinase in acute arterial occlusions after cardiac catheterization.

Arterial occlusions after cardiac catheterization are usually treated surgically. We report four patients with femoral thrombosis or distal emboli that developed after cardiac catheterization. Each patient was treated successfully with intravenous streptokinase. Therapy was initiated 1-60 hr after the procedure. The duration of infusion lasted 4-42 hr (mean 27 hr). Pulses were restored 4-19 hr (mean 10 hr) after the beginning of infusion. There was no major hemorrhagic complication, even in patients with very early streptokinase infusion. Thus intravenous streptokinase may be an alternate choice to surgery for arterial occlusions after invasive procedures.

Rebound of vasospastic angina after cessation of long-term treatment with nifedipine.

The beneficial effect of calcium antagonists in the treatment of vasospastic angina is now well recognized. Although withdrawal symptoms have been reported following abrupt cessation of therapy with some cardiovascular drugs, there is no detailed report on similar complications of the cessation of therapy with calcium antagonists. In a 4-month period eight patients with well documented and well controlled vasospastic angina experienced a marked increase in the frequency and duration of anginal episodes at rest following the involuntary cessation of treatment with nifedipine, 10 to 20 mg four times a day. The increase began within 2 to 5 days after the cessation of treatment. Substitute therapy with isosorbide dinitrate, 30 mg, and verapamil, 80 to 120 mg, each four times a day, was effective in all cases. Although the mechanism responsible for this rebound phenomenon is not known, awareness of its existence is essential considering the widespread use of calcium antagonists.

Anaerobic mediastinitis and septic shock secondary to esophageal perforation.

The authors report unusual complications arising from the ingestion of a small fish bone by a 68-year-old man. These included mediastinitis, empyema, pericarditis and septic shock, probably secondary to a small perforation of the esophagus. After appropriate surgical drainage, antibiotic therapy and supportive therapy the patient made a good recovery.

Efficacy of delayed percutaneous transluminal coronary angioplasty after intravenous use of streptokinase in myocardial infarction.

Between June 1984 and December 1986, 35 patients with acute myocardial infarction received streptokinase intravenously within 3 hours after the beginning of chest pain and underwent percutaneous transluminal coronary angioplasty (PTCA) either immediately (in 2 cases) or 1 to 19 (mean 4.4) days later (in 33). The rate of successful PTCA was 89%. Reocclusion occurred in one patient. The mean percentage of stenosis decreased from 86% to 11%. The mean trans-stenotic gradient was reduced from 41 to 11 mm Hg. The results suggest that in patients whose condition is stable, PTCA performed a few days after thrombolysis is a valuable alternative to more aggressive treatment with immediate PTCA.

The role of coronary thrombosis in myocardial infarction: further evidence shown by intracoronary thrombolysis with streptokinase.

Myocardial infarction is usually caused by a thrombus occurring on a significant coronary lesion. A 60-year-old male was admitted with an acute evolving anterior myocardial infarction. Three hours after the beginning of chest pain, the electrocardiogram showed ST-segment elevation in the anterior and lateral leads which persisted despite intravenous nitroglycerin (100 mcg/min). One hour later, an angiogram showed complete obstruction at the origin of the left anterior descending artery (LAD). After intracoronary streptokinase (250,000 units) the LAD opened and a 90% obstruction was seen at its origin. However, an anterior myocardial infarction occurred. One month later, an angiogram showed a slight irregularity at the origin of the LAD. Thus, this case demonstrates that 1) a myocardial infarction may occur with a near normal coronary artery, and 2) a thrombus may occur at the site of a slight coronary irregularity.