Effects of pentoxifylline on central hemodynamics in patients with congestive heart failure.

Pentoxifylline, a xanthine derivative with vasoactive and hemorheologic properties, was studied in regard to effect on central hemodynamics in ten patients with congestive heart failure due to aortic or mitral valve disease, mainly in NYHA group III or IV. The drug was infused intravenously in a dose of 4 mg/kg b.w. during a stable hemodynamic situation after valve replacement. The heart rate, systemic blood pressure, central venous and pulmonary artery pressures and cardiac output were recorded, and the stroke volume, cardiac index and systemic vascular resistance were calculated. Significant increase in cardiac output from the baseline value of 4.92 l/min was found 5-10 min (+22.6%) and 25-30 min (+19.5%) after pentoxifylline infusion. Cardiac index similarly increased from baseline, 2.73 dsc-5 (+22.3 and +18.3, respectively). The systemic vascular resistance showed significant decrease at the same intervals (-20.6 and -15.5%). The heart rate and stroke volume were significantly increased after 5-10 min. The systemic mean blood pressure and the pulmonary artery and central venous pressures showed no significant changes. There were no adverse effects of pentoxifylline.

Negative effects of dihydroergotamine (Orstanorm) on central haemodynamics and aorto-coronary bypass blood flow. An intraoperative study.

Dihydroergotamine (DHE), Orstanorm, because of its strong constrictor action on capacitance vessels, is used in the treatment of hypotension caused by orthostatism or spinal or epidural anaesthesia. Lately Orstanorm has also been used in combination with heparin as prophylaxis against postoperative thromboembolism. In the present study, Orstanorm (0.01 mg/kg b.w.) was given intravenously to 20 patients after coronary bypass surgery. Coronary bypass blood flow, heart rate, systemic mean and systolic blood pressures, right and left atrial pressures, pulmonary artery pressure and cardiac output were measured. Stroke volume, cardiac index, stroke index, systemic and regional myocardial vascular resistance and cardiac work index were then calculated. The results showed that despite increased filling pressures there was no rise in cardiac output, and despite increased cardiac work the bypass flow significantly decreased. The significant increase in regional myocardial vascular resistance found after administration of DHE may explain the absence of expected increase of cardiac output and coronary bypass flow.

The advantage of the thoraco-retroperitoneal approach for aortorenal bypass grafting.

Postoperative angiographic studies after aortorenal saphenous vein bypass grafting have revealed a high incidence of graft dilatation and aneurysms. The aortorenal bypasses in all these series were performed via the transabdominal approach which gives an angle of at least 90 degrees between the graft and aorta. The routine approach in the present study has been the thoraco-retroperitoneal one which has been used since more than 20 years in 189 patients. In 13 of them an aortorenal saphenous vein bypass was performed. The saphenous vein was sutured into the aorta above the orifice of the renal artery giving an acute angle of about 45 degrees. This angle gives much more favourable hemodynamic conditions including less turbulence. All the patients survived the operation and were followed for a mean period of 5 years. Two of the patients were hypertensive because of stenosis of the opposite renal artery. Eight patients are normotensive and three patients are improved. Renal arteriograms performed 4 to 13 years postoperatively in five of the patients showed excellent conditions without any dilatation of the graft. The thoraco-retroperitoneal approach gives a very good access to the entire renal artery and permits an aortorenal bypass with an angle which causes a minimum of turbulence.

Central, high flow subclavian artery-internal jugular vein fistula for venous access.

A subclavian artery--internal jugular vein shunt was created for intermittent parenteral infusions in six patients who had undergone extensive intestinal resection because of Crohn's disease or ulcerative colitis. The flow rates through the shunt were initially around 1000 ml/min. In three patients the flow later increased, giving rise to mild cardiac symptoms. Slight disturbance from arm ischemia during work was experienced by two patients. Some patients were disturbed by murmurs from the shunt when the flow increased. Narrowing of the vein at the end-to-side anastomosis diminished excessive flow and relieved symptoms. There was no perioperative mortality, and no septic, hemorrhagic or wound healing complications occurred in connection with the six primary and nine secondary operations. The patency rate of fistula was 100% after one year, 83% after two years and 66% after three years. The shunt was well accepted by patients and by personnel. This type of A-V fistula for intermittent parenteral infusions seems to be a feasible alternative to other A-V shunts when the usual vascular access routes have been exhausted.

Subclavian steal-carotid recovery phenomenon. Experience of 7 operated patients.

Subclavian steal-carotid recovery phenomenon, which accompanies an occlusion of the brachiocephalic trunk, is a rare cause of transient ischemic attacks. In the actual study, including 7 operated patients, preoperative symptoms, results of directional Doppler ultrasound examinations further evaluated by sonography, angiography, peroperative flowmetry and postoperative outcome are presented and discussed. Fits of vertigo, right-sided blindness and left-sided paralysis were the most common symptoms. Retrograde vertebral artery, antegrade common carotid and supraorbital artery blood flow was found by ultrasound. Analysis of the audio-frequency obtained by ultrasound revealed, however, preoperative abnormal flow of the common carotid artery. In 6 patients, angiography revealed retrograde vertebral but antegrade common carotid artery blood flow and in the 7th patient, both vertebral and common carotid artery blood flow was reversed. Peroperative flowmetry revealed increased retrograde blood flow of the vertebral and change from ante- to retrograde flow of the common carotid artery during hyperemia of the right arm. One patient died after 40 days due to sepsis, the focus of which was neither traced clinically nor at autopsy. One patient, who was free of preoperative symptoms, died after 4 years from myocardial infarct. Five patients are alive, 4 are completely free and another improved from the preoperative symptoms after 1-7 years.

Surgical management of obliterative disease of the brachiocephalic trunk. Experience from 24 cases.

Transsternal endarterectomy was performed in 24 patients for symptomatic obliterative disease of the brachiocephalic trunk in the period 1961-1981. In 10 of the patients the vessel was occluded, and in 14 there were various degrees of stenosis. Reversal of vertebral artery flow was found in 15 patients. Subclavian steal-carotid recovery phenomenon was present in six patients, and one patient had reversed flow in both the right vertebral and the common carotid artery. Only 10 of the 24 patients were free from obliterative changes in other extracranial arteries. After the reconstruction, the blood flow in the brachiocephalic trunk increased from 370 to 610 ml/min in patients with stenosis, and from 0 to 692 ml/min in patients with occlusion. The flow rate changed in the right vertebral artery from -58 to + 119 ml/min and in the right common carotid artery from 116 to 340 ml/min. Two patients died in the early postoperative period (8.5%) and six died during the follow-up period. Follow-up was possible in 21 patients. The result of endarterectomy was assessed as cure in 14, improvement in two and failure in three patients. Stroke occurred in two patients.

Monitoring direction of vertebral artery blood flow by Doppler shift ultrasound in patients with suspected "subclavian steal'.

A significant subclavian or innominate artery obliteration may cause reversal of flow in the ipsilateral vertebral artery causing vertebro-basilar ischaemia with cerebral symptoms, called the subclavian steal syndrome. Until recently, angiography was the only method of diagnosing a subclavian steal. In the present study, a non-invasive technique (Directional Doppler ultrasound) was used to determine the direction of flow in the vertebral arteries. The study was carried out on 22 patients referred with suspected subclavian could be identified bilaterally by the Doppler ultrasound technique, which also revealed unilateral retrograde in twenty and bilateral antegrade (= normal) vertebral artery blood flow in two patients. These findings were verified in all patients by aorto-cervical angiography. Seven of the patients then had their subclavian or innominate artery reconstructed. Postoperatively a new Directional Doppler ultrasound examination then showed bilateral normal (= antegrade) vertebral artery blood flow. The used non-invasive technique is shown to have high reliability and may be used to screen patients suspected of having subclavian steal pre-angiographically and preoperatively. The method is also of value for the post-operative control.

The effect of etilefrine (Effortil) on regional blood flow during arterial reconstructive surgery.

Etilefrine is a sympathomimetic amine with high affinity for alpha- and beta2-receptors. Following vascular reconstructions in 38 patients the effect of intravenously administered etilefrine on cardiac output, mean systemic blood pressure, blood flow and vascular resistance of the carotid, subclavian, mesenteric, iliac and femoral arteries was studied intraoperatively. Cardiac output and the mean systemic blood pressure were significantly increased. The blood flow was increased in all the arterial beds studied distribution. The peripheral vascular resistance was considerably decreased for the subclavian, iliac and femoral arteries' regions of supply but unchanged or increased for those of the carotid and mesenteric arteries. This discrepancy may be explained by the different effects of etilefrine on the vascular resistance of parenchymatous and of muscular regions, but it is also possible that the effect of etilefrine on the blood flow to the intestines and brain is counteracted by autoregulation.

Unusual indications for carotid artery surgery.

Nineteen patients with transient ischaemic attacks (TIA), selected from a series of 420 patients who underwent carotid endarterectomy during the last 10 years were studied. All had one occluded and one stenosed internal carotid artery with neurological symptoms from the contralateral brain hemisphere in relation to the stenosis. Carotid endarterectomy was performed on the stenosed side utilizing temporary bypass with continuous bypass blood flow measurements. The mortality was 5%. In 14 of 16 patients the symptoms disappeared postoperatively. The cause of the patients symptoms was probable embolization from the stenosed carotid artery to the contralateral hemisphere or episodes of ischaemia due to haemodynamic importance of the stenosis.

The effect of etilefrine (Effortil) on central hemodynamics and aorto-coronary bypass blood flow. A pre-operative study.

In an attempt to elucidate the function of an aorto-coronary bypass in patients with coronary artery obliterative disease, intravenous injection of etilefrine was used to bring about variations of central hemodynamics. Etilefrine proved to cause a significant increase of cardiac output (QPA), mean systemic blood pressure and aorto-coronary bypass flow. Calculations of peripheral myocardial resistance showed a rather pronounced decrease in all vascular regions studied. There was no change of central venous pressure. The decrease of the myocardial vascular resistance, as shown by the increase of aorto-coronary bypass flow, is indicative of the myocardial vascular capacity. Hence, it may be of value as a prognostic test.

Intrathoracic approach for subclavian and innominate artery reconstruction.

A subclavian or innominate artery obliteration may cause a retrograde flow in the vertebral artery, a subclavian steal. The steal has been associated with cerebral symptoms indicating vertebrobasilar ischaemia, the subclavian steal syndrome. As there still are no objective means of measuring the effect of the steal on the brain circulation, the syndrome can only be proved by experience from the results of surgical attempts to correct the steal. The steal was at first eliminated by direct reconstruction of the subclavian and innominate arteries through a thoracic approach. As the mortality was high, many surgeons have used cervical bypass procedures with considerably lower mortality. The present report is based on 15 years' experience with 85 patients operated on with direct artery reconstruction through a thoracotomy. A low mortality (1.3%) for the last ten years, a high patency of the reconstruction (80%) 8 years postoperatively and rather high rate of improvement (72%) in patients with subclavian steal syndrome were found. The study shows that the mortality rate with the thoracic approach need not necessarily be higher than with the cervical one. The high patency and the haemodynamically correct type of the reconstructions favour the thoracic approach. However, the direct reconstruction demands a technically advanced surgeon, who is well aquainted with the method. The results also showed that surgery still may be an alternative in patients with symptomatic subclavian steal.

Haemodynamic studies in renal artery stenosis.

With the aid of an electromagnetic flowmeter and a mechano-electrical pressure transducer, peroperative renal artery blood flows and pressures in the aorta and the renal artery distal to the stenosis were measured in 48 patients with renovascular hypertension before and after renal artery reconstruction. Calculations of pressure difference across the stenosis and resistances over the stenosis and the renal parenchyma were made. There was a significant blood flow increase through the renal artery after arterial reconstruction in all patients, irrespective as to whether they were normotensive, improved or failures postoperatively. The pressure difference across the stenosis after reconstruction was eliminated in all 3 groups of patients. The highest resistances over both the stenosis and the renal parenchyma before arterial reconstruction were found in the normotensive group, but there was no significant variation between the 3 groups. After reconstruction, a significant decrease in resistance over the renal parenchyma was found in the normotensive and the improved group of patients. The resistance of the stenosis was higher than over the renal parenchyma only in the postoperatively normotensive patients. This indicates that the removal of a resistance over the renal artery stenosis, that is higher than that over the renal parenchyma, gives the most favourable long-term results concerning normalization of the blood pressure.

Persisting hypertension after renal artery reconstruction. A follow-up study.

Twenty-four patients with persisting hypertension after renal artery reconstruction were re-investigated 1--8 years after surgery. They underwent renal arteriography, determination of plasma renin activity, renography and renal function studies in order to find the causes of the postoperative hypertension. Restenosis was found in 6 patients, in 3 of whom it was of functional significance according to the positive renin tests (renin ratio greater than 1.5). Positive renin tests were found in 2 other patients. One had occlusion of a renal artery branch and the other hypoplasia of the kidney due to chronic nephritis. No explanation of the persisting hypertension could be found in 19 patients at re-examination. In 10 of them, however, biopsy from the affected kidney obtained during operation showed nephrosclerosis, which may explain the outcome. Fourteen of the 19 patients had negative renin tests preoperatively. These negative tests indicate that renal artery stenosis was not the only cause of hypertension. It may be concluded that the renin test is of the utmost value in the selection of patients for renal artery reconstruction and should always be considered. A biopsy from the contralateral kidney may be necessary in order to detect other causes of hypertension than renal artery stenosis. The importance of re-investigating patients with persisting hypertension is confirmed by the present study.

Non-invasive methods of the evaluation of obliterative disease of the subclavian or innominate artery.

The preoperative investigation of 25 patients referred for evaluation of subclavian artery obliteration is reported. Non-invasive methods were used prior to angiography to assess arm circulation and the direction of blood flow in the vertebral artery. A retrograde flow in one vertebral artery was found in 18 patients, but only 7 had symptoms judged to be caused by the reversal of flow. In only one patient was the arm circulation so impaired as to justify the diagnosis of arm claudication. A high frequency of carotid lesions was found on the angiograms. The report demonstrates that in cases of suspected subclavian steal and/or arm claudication due to a subclavian artery obliteration, non-invasive methods should be used to screen the patients before angiography. In many cases it will be found that symptoms cannot be attributed to steal or impairment of the arm circulation and therefore angiography is not indicated. However, in some cases signs of a coexistent carotid lesion may still necessitate angiography.

Abdominal aortic aneurysms. 1. Selection of patients and operative results.

Between 1958--1976 204 patients with abdominal aortic aneurysms were admitted to the surgical ward for evaluation. One hundred and thirty-eight patients were operated on, 7 died prior to operation and 59 patients were not recommended operation for different reasons. Elective surgery was performed in 60 patients and 78 underwent acute surgery. The aneurysm had ruptured in 40 of the acutely operated patients. The operative mortality was 33% for the whole series, 65% among the ruptured aneurysms and 10% for the planned operations. The early mortality diminished successively and was during the last 5-year period 4% for planned and 40% for emergency operations. The main causes of the early mortality was renal or cardiac insufficiency and abdominal or gastrointestinal haemorrhage. Intestinal infarction was the cause of death in two patients. Twenty-nine re-operations were made in 24 patients. Abdominal haemorrhage, gastro-intestinal bleeding or arterial embolus in the leg were the most common reasons for the re-operations. An analysis of the factors that may influence the operative mortality revealed that age, sex, pre-operative shock, re-operations and number of blood transfusions may be of importance for prediction of the survival. Previously known hypertension, infarction, myocardial ischaemia or the operation time did not seem to have any predictive value. The most common reasons for not recommending surgery were small aneurysms, technical inoperability, advanced age or severely complicating disease.

Abdominal aortic aneurysms. II. Long-term follow-up of operated and unoperated patients.

Survival rate, causes of late death, employment, general health, walking capacity and sexual activity were investigated in 87 patients operated on for abdominal aortic aneurysms and 44 unoperated patients. The life expectancy was higher in the operated patients. The higher mortality for the non-operated patients was mainly due to aneurysmal rupture. Both groups of patients succumbed to atherosclerotic diseases, which before death had restricted their physical activity. More non-operated than operated patients left their employment due to the aneurysm disease. Eleven of 31 still living male operated patients had lost ability of erection postoperatively and 18 had abnormal or absent ejaculation. For the 12 still living non-operated patients indication for surgery was again considered and 3 of these patients will be recommended operation.

Renal artery reconstruction in renovascular hypertension.

Over a period of 8 years, 52 patients (31 females and 21 males) between 12 and 59 years of age (mean age 40 years) underwent renal artery reconstruction for correction of renovascular hypertension. Five patients were operated on bilaterally. A thoracoretroperitoneal approach was chosen at 48 of 57 renal artery reconstructions. The most used types of arterial reconstruction were thrombendarterectomy and vein patch, resection of the stenosis and end-to-end anastomosis, vein patch only or aortorenal vein bypass. No early or late nephrectomies were performed. These was no operative mortality, but 3 late deaths occurred. Twenty-two patients were normotensive postoperatively, 20 were improved and there were 10 failures. The follow-up time as 1--8 years. The blood pressures were measured after withdrawal of antihypertensive drugs for at least 10 days. The best predictable criterion for normotension was a positive renin test with a renin ratio of 1.5 or more. The normotensive patients were in the younger age group with a shorter duration of known hypertension and had mainly fibromuscular hyperplasia.

[Doppler ultrasound technique compared to angiography, intraoperative pressure gradients and blood flow measurements in carotid surgery (author's transl)]. / Vergleiche der Doppler-Ultraschallbefunde mit Angiographie-Befunden, intro-operativen Druckdifferenzen und Blutfluss-verhältnissen in der Karotischirurgie.

Doppler ultrasound technique was used in 32 patients to differentiate between non-signigicant stenosis, significant stenosis and occlusion of the internal carotid artery. The results were then compared to angiographic findings and peroperative pressure gradients and blood flow measurements. The Doppler examinations showed good agreement with the angiograms. Pathologic Doppler results were positively correlated to a high pressure gradient but were not correlated to the internal carotid blood flow. Pre- and postoperatively the Doppler ultrasound examinations increased the diagnostic security, improved the assessment of the hemodynamic significance of a stenosis and made in some cases an angiogram unnecessary.

Superior mesenteric artery and aorto-iliac blood flow after surgical reconstruction in the aortic bifurcation.

In order to evaluate the possibility of a redistribution of blood from the superior mesenteric artery to the iliac-femoral region, as a cause of intestinal gangrene after surgical reconstruction in the aortic bifurcation, 149 patients operated upon during the last 10 years were reviewed. Aorto-iliac blood flow was studied in all the patients. Blood flow measurements on the superior mesenteric artery before and after release of the aortic clamp and after intra-arterial injection of a vasodilator were made in seven patients. No intestinal complications were found in the present material. The superior mesenteric artery blood flow showed little or no variations and a redistribution of blood from the mesenteric artery to the iliac-femoral region can hardly explain intestinal necrosis.