Biomedical subjects

D F Guthaner

Publications and source records attributed to D F Guthaner.

11 recordsLinked to original sources

PubMed1979

Altered adrenergic activity in coronary arterial spasm: insight into mechanism based on study of coronary hemodynamics and the electrocardiogram.

To elucidate the pathophysiologic mechanism of coronary arterial spasm, the hypothesis was examined that underlying alterations in sympathetic activity may account for this syndrome in some patients. Observations were directed to alterations in coronary arterial hemodynamics and the electrocardiogram. Spasm of the left anterior descending coronary artery produced a mean increase in coronary vascular resistance of 107 percent (P less than 0.05) in four patients in whom coronary sinus blood flow was measured with the thermodilution technique. The alpha adrenergic blocking agent phentolamine, given intravenously, acutely reversed coronary spasm and its clinical manifestations in eight patients and reduced coronary resistance. In four patients, administration of the long-acting oral alpha blocking agent phenoxybenzamine (20 to 80 mg/day) caused disappearance of symptoms during a follow-up period of 3 to 12 months. Transient prolongation of the corrected Q-T interval preceded spontaneous or ergonovine maleate-provoked coronary spasm in 11 patients with variant angina pectoris, whereas no significant change in the Q-T interval followed ergonovine administration in 27 control patients with atypical chest pain who did not have coronary spasm. T wave inversions in the resting electrocardiogram were normalized by isoproterenol infusion in one patient and by long-term phenoxybenzamine treatment in four patients with variant angina pectoris. These Q-T and T wave changes are analogous to those described with unilateral or asymmetric stellate ganglion stimulation in animals. These observations suggest that alterations in the sympathetic nervous system that are consistent with asymmetric stellate ganglion activity and transient alpha adrenergic receptor stimulation can presage the development of coronary arterial spasm in some patients with variant angina pectoris.

Adult↗

PubMed1979

Fate of the false lumen following surgical repair of aortic dissections: an angiographic study.

Postoperative angiography was performed in 27 patients who had surgical repair for aortic dissections. The ascending aorta was involved in 22 dissections (Type A), while in five dissections it was uninvolved (Type B). Findings were assessed between two weeks and 13 years postoperatively. Despite the primary surgical objective to abolish flow in the false lumen, the majority of patients, whether symptomatic or not, continued to harbor patent distal false channels. In certain cases, one or more vital aortic branches were perfused solely by the false lumen. Initial postoperative angiography is indicated for determined surgical results as well as the functional significance of late angiographic findings, should symptoms recur. Further extension of the initial dissection, redissection, or enlargement of localized saccular aneurysms may mandate late reoperation. These conditions manifest themselves by pain, aortic regurgitation, neurological sequelae, or compromise of blood flow to a vital organ or extremity.

Aortic Dissection↗

PubMed1979

The effects of ergonovine maleate on coronary arterial size.

Changes in coronary arterial size due to ergonovine maleate are described and quantitated in 90 patients--18 with typical angina pectoris, 56 with atypical chest pain, nine with variant angina pectoris, and seven heart transplant (allograft) recipients. We observed two angiographic changes in the diameter of coronary arteries: 1) spasm, which was characterized by occlusion or marked (greater than 85%) focal or diffuse vessel narrowing, or 2) relatively mild and diffuse vessel narrowing, which was interpreted as the normal pharmacologic response to the drug. Serial bolus injections of 0.05 mg, 0.10 mg and 0.25 mg of ergonovine maleate produced diffuse narrowing of the diameter of coronary arteries of 10 +/- 1.5%, 16 +/- 1.4% and 20 +/- 1.3% (mean +/- SEM), respectively, in the 72 patients with anginal syndromes who did not develop coronary spasm. The degree of coronary arterial narrowing was the same in heart transplant recipients and in patients with normally innervated hearts who did not develop coronary spasm. We believe the normal pharmacologic response to ergonovine maleate was due to a direct vasoconstrictor action of the drug; this action was independent of neural control extrinsic to the heart.

Adult↗

PubMed1979

Long-term serial angiographic studies after coronary artery bypass surgery.

Twenty-six patients underwent repeat coronary angiography 5--8 years after saphenous vein coronary artery bypass surgery (SVCABG). These patients were selected from the first cohort of 117 patient who had SVCABG because they had obtained essentially complete relief of angina, and because all grafts were patent at initial angiography 11.2 months (mean) after surgery. Of the 39 grafts (1.5 grafts per patient) patent at 1 year, 34 (87.2%) were patent at reexamination 76 months (mean) (range 65--103 months) after SVCABG. Graft occlusion could not be predicted by the early angiographic appearance of the graft itself or its proximal or distal anastomosis. In some cases, narrowing or irregularity consistent with intimal hyperplasia appeared to progress, while in others it developed at late follow-up. Progressive narrowing occurred in 96% (22 of 23 grafted vessels) of the native coronary arteries proximal to the graft anastomosis. Progresssion to a stenosis greater than 75% or total occlusion was seen distal to the graft anastomosis in eight of 39 grafts (20%). Of 103 non-bypassed major vessels, 56% showed some progression of disease and half of these progressed to significant stenoses (greater than 75% luminal narrowing). There were no apparent predictors to indicate whether progression in nongrafted coronary arteries would occur preferentially in a previously stenotic or nonstenotic vessel, although 80% of vessels with initial stenoses greater than 75% progressed to total occlusion.

Adult↗

PubMed1979

CT demonstration of cardiac structures.

Cross-sectional cardiac anatomy was studied by computed tomography (CT) in normal patients and in patients with well documented cardiac pathology. Specific cardiac chambers, aortic and pulmonary artery enlargement, ventricular aneurysms, coronary artery, and intracardiac calcifications were demonstrated using a 3 sec scan time with and without intravenous iodinated contrast media. Although CT imaging of the heart is in its infancy, the clarity with which cardiac chambers and other structures were visualized is encouraging and suggests the potential value of CT scanning for detecting significant intracardiac pathology on routine thoracic CT scans.

Aortography↗

PubMed1978

Organized left atrial mural thrombus demonstrated by coronary angiography.

Small coronary artery fistulas terminating at the site of adherent, organized mural thrombi in the left atrial appendage were observed during selective coronary angiography in patients with mitral stenosis. The angiographic features of this abnormality can be distinguished from those of cardiac tumors, vascular malformations, and coronary artery fistulas that are not associated with organized thrombus. This coronary angiographic abnormality may indicate the presence of left atrial thrombus that is not revealed by echocardiography and is not manifest clinically by systemic emboli. The size of the collection of radiographic contrast material in the left atrium is not proportional to the size of the thrombus.

Aged↗

PubMed1978

Critical aortic stenosis in neonates.

Twelve infants with valvular aortic stenosis manifested symptoms of heart failure during the first 2 months of life. Nine became symptomatic and demonstrated cardiomegaly and pulmonary vascular congestion during the first week of life. The other 3 infants became symptomatic at 3-8 weeks. Echocardiograms revealed normal or enlarged left atrial and ventricular dimensions excluding hypoplastic left heart. Left ventriculography demonstrated segmental dysfunction in 7 infants and generalized hypokinesis in 2 others. Trabecular effacement corresponded with the sites of left ventricular dysfunction. Postoperative studies revealed a decrease in cardiac size and improvement in segmental dysfunction in most infants.

Aortic Valve Stenosis↗

PubMed1978

Recurrent mediastinal bronchogenic cyst. Cause of bronchial obstruction and compression of superior vena cava and pulmonary artery.

The recurrence of a benign mediastinal bronchogenic cyst 20 years after partial excision precipitated potentially serious vascular and pulmonary complications. Aggressive total surgical excision should be feasible in the majority of cases. An approach via a median sternotomy offers distinct advantages in certain cases and should be considered. Computerized axial tomographic scanning promises to provide improved definition of mediastinal anatomic features and should be a valuable noninvasive diagnostic method in selected cases.

Bronchial Diseases↗

PubMed1978

External iliac artery fibrodysplasia.

Clinical and arteriographic features of 12 patients with external iliac artery fibrodysplasia are reviewed. These lesions usually occur in patients having arterial fibrodysplasia elsewhere, attesting to the fact that they represent a generalized arteriopathy. Occasionally they occur in association with severe atherosclerosis. External iliac artery fibrodysplasia exhibits the classic corrugated "string-of-beads" angiographic appearance in the majority of patients. The pattern of aneurysmal dilatation of the external iliac arteries in one patient and the aorta and common iliac and internal iliac arteries in another with diffuse arterial fibrodysplasia has not been previously reported. Three patients had symptoms directly referable to external iliac artery fibrodysplasia. The lesions may be symptomatic when the arterial lumen is sufficiently compromised to reduce blood flow or when superimposed thrombosis and/or embolization occurs.

Adult↗

PubMed1977

Stop-action cardiac computed tomography.

Computed tomographic (CT) cardiac imaging in vivo has been hampered by motion of the heart during its cardiac cycle. A technique of post data-acquisition correlation of the angular projection data using the electrocardiogram as a reference signal is described. This method produced seven "stop action" images of the heart and resulted in delineating morphological detail not recognizable on the conventional CT scan.

Electrocardiography↗

PubMed1977

Intraarterial analgesia in peripheral arteriography.

A pilot study involving 36 patients was undertaken to test the efficacy of combining 1% lidocaine with 60% methylglucamine iothalamate for relief of the severe burning pain often experienced during peripheral arteriography. Of 24 patients premedicated with meperidine hydrochloride and promethazine hydrochloride, 12 received lidocaine with the contrast medium and 12 did not. The remaining 12 patients were premedicated with diazepam and received lidocaine with the contrast material. By both subjective and objective criteria, those patients receiving lidocaine in the intraarterial injection of contrast medium suffered less pain. Optimum results were achieved for the lidocaine group receiving analgesic premedication. No adverse reactions attributable to the lidocaine were encountered. Subsequent to completion of the pilot study, more than 300 patients have been studied with similar impressive results of pain relief and safety.

Analgesia↗