Anatomical mismatch of the pulmonary autograft in the aortic root may be the cause of early aortic insufficiency after the Ross procedure.

OBJECTIVE: Early aortic insufficiency can be a problem after the Ross procedure. Anatomical mismatch and an inexact surgical technique may lead to distortion of the normal pulmonary valve geometry and subsequent incorrect leaflet coaptation and valve insufficiency. In this study, we assessed the efficacy of changing and improving the surgical technique to minimize the early pulmonary autograft valve failure. The modifications and the strategy are discussed. METHODS: From January 1995 to February 1999, a total of 77 adults underwent the Ross procedure for aortic valve replacement at Sahlgrenska University Hospital. The operative technique used was full free-standing aortic root replacement with a pulmonary autograft in all cases. In the first 24 cases, the diameter of the pulmonary roots was seldom measured, eye-balling was used to exclude anatomical mismatch due to a dilated aortic root, and only one attempt of correction was made, which failed. In the other 53 cases, the technique was improved by: (1) reducing the aortic anulus diameter in cases with moderate dilatation; (2) excluding cases with severe dilatation of the aortic annulus; (3) adjusting the diameter of the sinotubular junction of the aorta to the diameter of the sinotubular junction of the pulmonary artery; (4). reimplanting the left ostium in the autograft, and (5) changing the proximal anastomosis technique. RESULTS: In this study, we had an early aortic incompetence of grade 2 in eight patients among the first 24 patients. In the other 53 patients, postoperative echocardiography at 1 week revealed aortic insufficiency of grade 2 in two patients. CONCLUSIONS: Aortic insufficiency after the Ross procedure can be minimized by patient selection, intraoperative correction of anatomical mismatch and improved surgical technique.

[A case report. Endometriosis caused colonic ileus, ureteral obstruction and hypertension]. / Fallbeskrivning. Endometrios orsakade kolonileus, uretärobstruktion och hypertoni.

Laparoscopy and palpation offer only a rough estimate of the extent of endometriosis. Consequently, endometriosis involving the bowels and urinary tract is under-diagnosed. Bowel obstruction and retroperitoneal endometriosis with obstruction of the ureter are uncommon conditions, but awareness of them is important. Ureteric obstruction develops slowly from periureteral fibrosis and often results in an asymptomatic hydronephrosis, loss of renal function and hypertension. Although renography is the first line of choice in investigation of the upper urinary tract in cases of suspected ureteric obstruction, ultrasound of the kidneys may be useful in the hands of the experienced gynecologist as a screening tool at consultation. The rationale for this recommendation is that ureteric obstruction and hydronephrosis often occur simultaneously. We present a case with bowel obstruction mimicking sigmoid carcinoma, ureteric obstruction and hypertension, caused by endometriosis, where the diagnostic difficulties are illustrated. Collaboration between gynecologist and urologist is essential in selected cases of endometriosis.

[Policy document. Catheter-based diagnosis and treatment of coronary diseases]. / Policydokument. Kateterburen diagnostik och behandling av kranskärlssjukdom.

Diagnostic coronary angiography and percutaneous coronary interventions (PCI) are rapidly developing fields. In-house thoracic surgery backup is no longer a prerequisite for PCI. The demand for physicians trained in interventional cardiology has created a need to formalise such education. The Swedish societies of cardiology and thoracic radiology have agreed on a policy document establishing the details of this education. It is the responsibility of the tutor to decide when the pupil has achieved adequate skills.

The effects of propofol on cerebral blood flow velocity and cerebral oxygen extraction during cardiopulmonary bypass.

UNLABELLED: We investigated the effects of burst-suppression doses of propofol on cerebral blood flow velocity (CBFV), cerebral oxygen extraction (COE), and dynamic autoregulation in 20 patients undergoing cardiac surgery. The experimental procedure was performed during nonpulsatile cardiopulmonary bypass (CPB) with stable hypothermia (32 degrees C) in fentanyl-anesthetized patients. Middle cerebral artery transcranial Doppler flow velocity, right jugular bulb oxygen saturation, and jugular venous pressure (JVP) were continuously measured. Dynamic autoregulation was tested by stepwise changes in mean arterial pressure (MAP) within a range of 40-80 mm Hg by sodium nitroprusside and phenylephrine before (control) and during propofol infusion, with a stable plasma concentration (approximately 9 microg/mL). Propofol induced a 35% decrease in CBFV (P < 0.0001) and a 10% decrease in COE (P < 0.05) compared with control. The slopes of the curves relating CBFV and COE to cerebral perfusion pressure (CPP = MAP - JVP) were less pronounced with propofol (P < 0.01 and P < 0.05, respectively). We conclude that propofol decreases CBFV and improves dynamic autoregulation during moderate hypothermic CPB. Furthermore, during propofol infusion, cerebral blood flow was in excess relative to oxygen demand, as indicated by the decrease in COE. IMPLICATIONS: In this study, we evaluated the effects of propofol on continuously measured cerebral blood flow velocity (CBFV) and cerebral oxygen extraction as a function of perfusion pressure. Propofol induced 35% and 10% decreases in CBFV and cerebral oxygen extraction, respectively. The slope of the curve relating cerebral perfusion pressure to CBFV decreased with propofol.

Social network, social support and the concept of control--a qualitative study concerning the validity of certain stressor measures used in quantitative social epidemiology.

Twenty-five in-depth interviews were made with middleaged persons of both sexes, who had suffered a first myocardial infarction (MI) two months previously. The purpose was to assess the layman's understanding of concepts such as social network, social support and control which are exposures commonly used or suggested for use in quantitative research in the area of social epidemiology. The validity of the instruments and the underlying concepts in assessing such exposures has important implications for the interpretation of the association between psychosocial factors and health or health behavior. The layman's understanding of social network and social support concepts seemed unproblematic, but the concept of control was understood in rather disparate ways among those interviewed. The experience of control/decision latitude in the work environment, seemed to form a model for the overall understanding of control among several of those interviewed and there also seemed to be important differences based on gender. Another impression, was that the individual's level of aspiration might be an important confounder in the assessment of control in population studies. It is therefore suggested that epidemiologcal data should be stratifyed by basic demographic variables like age, sex and social class in analyses including the control variable, to improve the valid use of this type of measure.

The relationship between the transfer factor obtained at rest, and arterial oxygen tension during exercise, in patients with miscellaneous pulmonary diseases.

Forty-one consecutive patients with the symptom 'exertional dyspnoea' were referred to the Department of Clinical Physiology for evaluation. Pulmonary fibrosis and chronic obstructive pulmonary disease were the most common diagnoses but other diagnoses were also represented. Some patients had no clinical diagnosis or radiological signs. All patients underwent exercise testing with sampling of arterial blood for blood gas analysis and pulmonary function testing including measurement of the transfer factor (carbon monoxide diffusing capacity) at rest. Independent of spirometric findings and diagnosis a significant correlation (r = 0.80, P < 0.001) was shown to exist between the transfer factor measured at rest and the arterial oxygen tension at maximal exercise level. We recommend measurement of the transfer factor as a screening test for exertional hypoxaemia and suggest that exercise blood gas analysis only seems necessary in patients with a transfer factor between 55% and 80% of the predicted value.

Social network and social support predict improvement of physical working capacity in rehabilitation of patients with first myocardial infarction.

A cohort of 50 patients under 70 years of age who had suffered their first myocardial infarction (MI) entered an exercise-based rehabilitation programme. An extensive personal interview concerning psychosocial factors, including social network and social support, as well as an assessment of an array of clinical and laboratory variables was made before the patients were discharged from the hospital. A follow-up 6 months later of the 40 patients that completed the programme showed that material social support and social anchorage at baseline predicted improvement in physical working capacity, independently from age, gender and important clinical variables. The authors conclude that psychosocial factors could be predictors of equal importance as many of the standard risk factors and clinical assessments in the rehabilitation of a majority of post-MI patients. It is suggested that training programmes should provide opportunities for involvement of the patients' social network, in order to benefit from optimal social support during the rehabilitation process.

Cardiovascular effects of nitroglycerin as evaluated by radioisotope methods.

Radioactive methods have successfully been used to elucidate the cardiovascular effects of nitroglycerin for decades. Xenon-clearance and the single probe technique were originally used to measure changes in myocardial flow caused by sublingual nitroglycerin. Later, similar studies were performed using the Anger camera permitting observations on regional myocardial flow. Microsphere techniques contributed to a better understanding of myocardial distribution of capillary flow. Modern methods in nuclear cardiology such as myocardial scintigraphy and gated blood pool scanning have shown their usefulness in demonstrating the cardiovascular effect of nitroglycerin on cardiac performance. The potential use of these non-invasive methods to study nitroglycerin effects is discussed.

Comparison of atrial pacing and the cold pressor test in patients with angina pectoris.

A haemodynamic and myocardial metabolic study was performed to compare effects of maximal atrial pacing and the cold pressor test (CPT) in patients with angina pectoris. Twelve patients (group I) had angiographically severe coronary artery disease, while 16 patients (group II) had normal coronary angiograms. At maximal pacing, angina developed in all patients in group I, and myocardial lactate production was found in eight of 12 patients. In group II, 12 out of 16 patients experienced chest pain, but only two patients had myocardial lactate production. Neither angina nor myocardial lactate production was present in any patient in either group during CPT. Coronary sinus flow increased and coronary vascular resistance decreased significantly in both groups at maximal pacing (P less than 0.001). At CPT, coronary flow decreased (P less than 0.05) and coronary resistance increased (P less than 0.001) in group I, while individual response was more variable in group II. In conclusion, maximal pacing was a more effective method of provocation of angina pectoris than CPT. The reactions of coronary sinus flow and coronary vascular resistance were different in group I than in group II. However, because of the variability of response in patients with normal coronary arteries, CPT cannot be used to distinguish patients with coronary artery disease from patients with no such disease.

Non-invasive determination of the distribution of cardiac output in man at rest and during exercise.

The distribution of cardiac output, as expressed by the regional uptake of thallium-201 following injection, has been studied by whole body scanning with a gamma-camera in six healthy persons and eight patients with aortic valvular disease. In the patients, cardiac output at rest and during exercise was also measured by the dye dilution technique. Combining the values of cardiac output and regional thallium uptake enabled the calculation of organ blood flow. The myocardial uptake of thallium at rest was 3.2 +/- 0.32% in the control group, which is significantly lower than 8.3 +/- 1.52%, found in the patients. The corresponding values measured in the kidneys were 12.5 +/- 1.91% in the healthy subjects and 7.1 +/- 0.50% in the patient material. Myocardial uptake increased and kidney uptake decreased in both groups following injection at peak exercise. Thallium uptake in the legs increased from about 13% at rest to about 39% at exercise in both groups. Distribution of thallium after injection at peak exercise did not, however, vary significantly between the two groups in the kidneys, abdominal area or the legs. Further methodological work is required before it can be ascertained to what extent the regional thallium uptake reflects the distribution of cardiac output. We nevertheless propose that the technique should be explored further, since it appears to be a simple non-invasive means of visualizing the distribution of the cardiac output in man under certain conditions.

Comparison of left ventricular ejection fraction assessed by radionuclide angiocardiography, echocardiography and contrast angiocardiography.

The left ventricular ejection fraction (EF) obtained by first pass radionuclide angiocardiography was compared with that determined by contrast angiocardiography in 49 patients. In 35 of the patients a comparison with the EF obtained by M-mode echocardiography was also made. The EF echo was determined in two ways, from the standard cube formula and the regression equation suggested by Teichholz for left ventricular volume calculations. The latter formula gave an average EF closer to the average EF obtained by isotope technique and cineangiography and was therefore used in the comparison study. Measurements of EF by isotope technique and echocardiography correlated well (r = 0.78). The correlation between these two noninvasive methods for EF determination and their cineangiographic counterpart was almost identical (r = 0.72--0.74).

Cardiovascular and neurological function in elderly patients sustaining a fracture of the neck of the femur.

Cardiac and neurological functions were evaluated at the time of operation in 81 randomly selected elderly patients who had sustained a fracture of the neck of the femur. Although only one-fifth of the patients had clinical signs of senile dementia or cerebrovascular disease on admission to hospital, more than half had seriously abnormal EEGs including 12 of the 15 patients who died within six months. ECGs before operation showed that patients with signs of arrhythmia or previous myocardial infarction had a much lower survival rate than those with normal or other pathological ECG signs. Nerve conduction velocity findings proved inconclusive when correlated with survival or return home. Routine EEG and ECG examinations are of value in detecting underlying dysfunctions which may not be observable clinically on admission but are important prognostic indicators for survival or return home, and may be implicated as causative factors of fracture in the elderly.

The use of thallium-201 myocardial scintigraphy for the diagnosis of previous infarction.

The ability of thallium-201 scintigraphy to detect previous infarction (greater than 6 months ago) was studied in 43 patients with coronary artery disease, 39 with valvular heart disease, and 5 with cardiomyopathy or myocarditis. All patients had undergone selective coronary arteriography and left ventricular angiography. Thallium-201 scintigraphy at rest proved a very sensitive method for detecting previous infarction, also clinically silent. Scintigraphy was more sensitive than a recent ECG. However, scintigraphy can give falsely positive results.

Distribution of intravenously injected 201thallium in the legs duging walking. A new test for assessing arterial insufficiency in the legs.

There is a multitude of method for assessing the efficiency of the arterial circulation in the legs. Most of these methods can give conclusive information about the patency of the main arteries in the leg; the level of an arterial obstruction can also be estimated. However, none of these methods provides a direct estimate of the functional importance of arterial lesions of light to moderate severity. The present report describes preliminary findings of the distribution of intravenously injected 201Thallium, a potassium analogue, in the legs during exercise provoking symptoms of ischemia. From this pilot study the general impression is that the thallium uptake pattern corresponds well with the clinical, physiologic, and angiographic picture.

Double-blind comparison of verapamil and practolol in the treatment of angina pectoris.

In thirteen patients with coronary insufficiency and angina pectoris the therapeutic effects of verapamil, 80 mg three times/day and practolol, 100 mg three times/day, were compared and tested against placebo in a double-blind cross-over fashion. Verapamil proved to be the most efficient drug as regards attack frequency and glyceryl trinitrate consumption as well as physical working capacity, bringing about a statistically significant increase of the exercise tolerance as compared to placebo after a treatment period of four weeks. Verapamil is a good alternative to beta-blockers in the prophylactic treatment of angina. Possible modes of action of verapamil in angina pectoris are discussed. The study had to be interrupted because of the reports of side effects of practolol, explaining the small number of patients.

Myocardial scintigraphy as a supplementary diagnostic tool in heart disease.

Myocardial scintigraphy with cesium-131 and thallium-201 was performed in 191 patients. Previous myocardial infarctions localized to the anterior and lateral wall of the left ventricle were correctly diagnosed with both radionuclides. Inferior and posterior infarctions were only detected when thallium was used. In patients with non-informative ECG changes like bundle branch block, non-specific ST-T changes or with atypical symptoms, myocardial imaging made an essential contribution to the establishment of a correct diagnosis. The potential value of myocardial imaging in patients with valvular heart disease and in cardiomyopathy is described.

Cardaic arrhythmias in chloral hydrate poisoning.

In three patients admitted to hospital after ingestion of an overdose of chloral hydrate, the ECG showed supreventricular and ventricular tachyarrhythmias. The possible mechanism for the arrhythmias may be an enhanced automaticity of supraventricular and ventricular pacemaker cells caused by metabolites of chloral hydrate. The ventricular arrhythmia responded to i.v. treatment with lignocaine in one patient, and to phenytoin in another in whom lignocaine failed to restore a normal sinus rhythm.