Biomedical subjects

J P Bagger

Publications and source records attributed to J P Bagger.

At least 55 records · Page 3Linked to original sources

PubMed1996

Diagnostic value of esophageal studies in patients with angina-like chest pain and normal coronary angiograms.

OBJECTIVE: To study 1) variations in esophageal motility and pH values and 2) electrocardiographic ST-segment changes in patients with angina-like chest pain but normal coronary angiograms. DESIGN: Cross-sectional study. SETTING: Tertiary cardiologic referral center. PATIENTS: 63 consecutive patients referred to the study center over a 3-year period and 22 healthy controls. Patients were grouped according to the results of exercise electrocardiography: normal response to exercise (n = 28) and ischemic response to exercise (n = 35). MEASUREMENTS: 1) 24-hour three-channel esophageal manometry and two-channel pH monitoring, 2) provocation testing with intravenous edrophonium chloride and esophageal acid perfusion, and 3) Holter electrocardiography conducted during the first two tests. In conventional time-weighted analyses, values during periods of pain and the 2 minutes before pain developed were compared with baseline values. RESULTS: Regardless of the outcome of exercise testing, no differences were seen in 24-hour esophageal variables between patients and controls. Forty-six patients had a total of 248 spontaneous episodes of chest pain. Only minor differences were seen between baseline and the prepain and pain periods. Edrophonium chloride provocation and acid perfusion caused chest pain in 9 patients (14%) and 10 patients (16%), respectively. Esophageal monitoring variables did not differ between patients with a positive response to one or both provocation tests (n = 16 [25%]) and controls and did not change between baseline and the prepain or pain perioids. Forty-eight ST-segment depressions were recorded on Holter monitoring in 16 patients (25%), but these depressions were associated with one prepain period and four pain periods. No ST-segment changes were seen during esophageal provocation testing. CONCLUSION: The rationale for routine esophageal investigations in this patient group is questionable.

Adolescent↗

PubMed1996

[Sick sinus syndrome. Pacemaker with atrial versus ventricular stimulation].

In patients with sick sinus syndrome, single chamber atrial pacing has been reported in retrospective studies to be associated with lower frequencies of atrial fibrillation, thromboembolism, heart failure, and mortality than ventricular pacing. We did a prospective randomised trial in 225 consecutive patients (142 women, 83 men; mean age 76 years) with the sick sinus syndrome, randomised to atrial (n = 110) or ventricular (n = 115) pacing and followed for up to five years (mean 40 [SD 18] months). During follow-up, the frequency of atrial fibrillation was higher in the ventricular group. Thromboembolic events (stroke or peripheral arterial embolus) occurred in 20 patients in the ventricular group and in six patients in the atrial group (p = 0.008). Twenty five patients died in the ventricular group compared with 21 in the atrial group (p = 0.74). The number of cases of heart failure did not differ between the two groups. Atrioventricular block occurred in two patients in the atrial group. It is concluded that patients with sick sinus syndrome should be treated with atrial pacing rather than ventricular pacing because atrial pacing is associated with lower frequencies of atrial fibrillation, thromboembolic complications, and a low risk of atrioventricular block.

Aged↗

PubMed1996

Porcine coronary artery pharmacodynamics in vitro evaluated by a new intravascular technique: relation to axial stretch.

A new intravascular balloon catheter-based technique, impedance planimetry and the wire-mounted isometric tension technique commonly employed to study vessel pharmacodynamics in vitro, were compared. Porcine left anterior descendent coronary artery reactivity to nifedipine was assessed and the influence of 20% axial stretch was investigated. There were no histological differences between segments where the impedance planimetry balloon had been inflated and untouched segments. EC50 values differed significantly between the three procedures applied: The isometric method (n = 7): 2.54 +/- 0.44.10(-9) M; nonstretched arteries by the impedance planimetric method (n = 7): 1.99 +/- 0.40.10(-8) M; arteries 20% axially stretched (n = 7): 2.00 +/- 1.36.10(-7)M (isometric and nonstretched: p < 0.05; isometric and stretched: p < 0.001; nonstretched and stretched: p < 0.05). Maximal relaxant responses to nifedipine were 91.8 +/- 2.1% (isometric method), 105.1 +/- 2.3% (nonstretched), and 104.9 +/- 7.7% (stretched) (ANOVA, p = 0.11). In stretched arteries, the initial 12-min response to an increased dose of nifedipine was more rapid than the response of nonstretched arteries at a concentration of 1.10(-7) M (p = 0.038) and had a nonsignificant tendency toward a more rapid response at other concentrations. Resting tone could not be demonstrated and time control experiments showed no change in the maximal vessel response to potassium with any of the three methods. A new method in the evaluation of artery pharmacodynamics in vitro was presented. The study demonstrated that axial stretching of an artery has impact on the pharmacodynamic reactivity to nifedipine in porcine coronary arteries. Further studies are needed to evaluate the impact of the method on endothelial function.

Animals↗

PubMed1996

Distal oesophageal motility characteristics in relation to amplitude of contraction in healthy persons.

OBJECTIVES: We wanted to supply a new 'vertical' approach in the analysis of oesophageal contraction data by describing variables of oesophageal function in relation to the amplitude of contraction. METHODS: Twenty-four-hour oesophageal manometry was performed in 20 healthy volunteers (11 women and 9 men; mean age, 47.5 years). Computer analysis was performed in pressure windows at 10, 15, 20, 30, 40, 50, 60, 70, and 80 mm Hg. Within each window two variables were extracted: the distribution (%) of peristaltic contractions and median duration (sec) of contractions. RESULTS: The percentage of peristaltic contractions increased with increasing amplitude of contractions during the upright position (15-20 mm Hg window: mean (+/- SD) 68.2% (+/- 13.3%), versus 70-80 mm Hg window: 85.0% (+/- 13.0%) (P < 0.001)) and meal periods (66.9% (+/- 13.8%) versus 92.2% (+/- 11.2%) (P < 0.001)) but not in the supine position (75.9% (+/- 14.6%) versus 73.5% (+/- 16.1%) (P = 0.64)). Contraction duration diminished with increasing contraction amplitude (upright, 15-20 mm Hg window: 3.2 sec (+/- 1.5 sec) versus 70-80 mm Hg window: 1.5 sec (+/- 1.0 sec) ( P < 0.0001); meal: 3.8 sec (+/- 1.7 sec) versus 1.9 sec (+/- 1.1 sec) (P < 0.01); supine: 4.1 sec (+/- 3.0 sec) versus 2.2 (+/- 1.5 sec) (P = 0.03)). The percentage of peristaltic contraction was lower during the supine periods than during meals and upright periods at high amplitudes (70-80 mm Hg window; P < 0.05). The number of contractions decreased linearly on a logarithmic scale with pressure window amplitude. CONCLUSIONS: Pressure wave amplitude and organization were closely related. Accurate base-line determination and delineation are critical for the interpretation of oesophageal manometric recordings.

Adult↗

PubMed1996

Twenty-four-hour ambulatory blood pressure and vasoactive hormones in valvular aortic disease.

The aim of this study was to assess the blood pressure profile and vasoactive hormones in valvular aortic disease. Thirteen aortic stenosis and/or aortic regurgitation patients were matched with 13 control subjects. Ambulatory blood pressure monitoring was performed for 24 h. Arterial and venous plasma concentrations of renin, angiotensin II, aldosterone, arginine vasopressin, atrial natriuretic peptide, immunoreactive endothelin and cyclic-GMP were measured. The mean 24-h blood pressure was higher in the patient group (94.9 mmHg) compared with control subjects (88.2 mmHg) (p < 0.0001), despite no differences in daytime blood pressures. The nocturnal blood pressure fall was attenuated in the patients (systolic/diastolic blood pressure -8.5/-3.5; -20.3/-14.3 mmHg (p < 0.001/p < 0.01)); in heart rate too the nightly fall was blunted in the patients (-4.8/ -13.4/min (p < 0.0013)). PRA, Ang II, AVP, ANP, ir-ET and cGMP were significantly increased in the patients compared to the controls. Nightly systolic blood pressure fall was inversely related to arterial (r = -0.75, p < 0.003) and venous (r = -0.65, p < 0.04) plasma renin activity and arterial aldosterone (r = -0.64, p < 0.05) in valvular aortic disease patients. In conclusion, valvular aortic disease patients have attenuated falls in blood pressure and heart rate during the night. Increased activity in the renin aldosterone system may be involved in this abnormal blood pressure regulation.

Adult↗

PubMed1996

In vivo assessment of luminal cross-sectional areas and circumferential tension-strain relations of the porcine aorta.

UNLABELLED: The objectives were to measure the pressure--cross-sectional area relations and intrinsic stiffness of the porcine aorta in vivo. METHODS: Measurements were made in 12 pigs, weight 30, 50 or 75 kg, proximal and distal to the bifurcation of the renal arteries, using an electrical impedance system which was located inside a balloon mounted on a catheter. Vessel cross-sectional area (CSA) was assessed by measuring impedance of the fluid inside the balloon during distension. RESULTS: In vitro testing demonstrated the accuracy and reproducibility of impedance planimetry. In vivo steady-state CSA values showed non-linear relationship with rising distension pressures. Mean CSA values rose with increasing weight of the pigs. the suprarenal aorta was larger than the infrarenal only in 75 kg pigs (p < 0.05). At three measurements the within-subject variation was 0.89% and the between-subject variation 99.11%. Nitroglycerine infusion produced only minor, insignificant CSA increase, indicating negligible tone in the abdominal aorta. All segments showed circumferential wall strain-tension relations with exponential behaviour uninfluenced by weight class or site in the aorta. CONCLUSION: Information of vascular mechanics in vivo is obtainable by catheterization of the abdominal aorta.

Analysis of Variance↗

PubMed1995

[Dynamic cardiomyoplasty. A possible surgical treatment of heart failure].

Dynamic m. latissimus dorsi cardiomyoplasty was introduced in 1985 as a new surgical treatment of terminal heart failure. The latissimus dorsi muscle is wrapped around the heart and paced simultaneously with the heart beat in order to contribute to the systolic function of the failing heart. Although more than 200 patients have received this treatment, the results show a persistent high perioperative mortality (16-25%). However, some patients achieve a considerable improvement in both survival and function, despite the fact that only a minimal improvement of cardiac function can be shown. The advantage of dynamic cardiomyoplasty is that the patient can be operated on in a stable phase. Also, as opposed to heart transplantation, there is no need for immunosuppression. Until further experimental and clinical documentation is available, dynamic cardiomyoplasty is not a realistic alternative to the established surgical and medical treatment of heart failure in Denmark.

Cardiomyoplasty↗

PubMed1995

[Intracoronary ultrasonography--a supplement to coronary arteriography].

Intracoronary ultrasound is a new technique, by means of which it is possible for the first time to visualise coronary artery wall structures in vivo. Compared to conventional coronary angiography the advances of this new modality appear to be: 1) Improved diagnosis of minimal and non-obstructive atherosclerosis; 2) Characterisation of plaque morphology, thereby being an aid in decision on interventional procedures (PTCA, atherectomy, stent placement); 3) Better delineation of coronary artery lumen area, which improves the accuracy of stenosis graduation both before and after interventional procedures. The examination can be performed in up to 95% of cases. The procedure appears to be safe with a reported complication rate of myocardial infarction and bypass surgery of 0.16% in 1837 cases; transient coronary artery spasms occurred in about 3%. Complications are predominantly associated with interventional procedures. Although intracoronary ultrasound has mainly been used for research purposes, results of ongoing trials assessing its clinical utility, as well as technological improvement providing more consistent image quality, suggest that the procedure will evolve into an important adjunct to coronary angiography.

Coronary Angiography↗

PubMed1995

Long-term effects of angiopeptin treatment in coronary angioplasty. Reduction of clinical events but not angiographic restenosis. European Angiopeptin Study Group.

BACKGROUND: Angiopeptin is a cyclic octapeptide analogue of somatostatin that has been shown to limit myointimal thickening of arteries in balloon injury models and to restore the vasodilating response to acetylcholine. A randomized, double-blind placebo controlled trial was conducted to assess the effect of angiopeptin in restenosis prevention after percutaneous transluminal coronary angioplasty (PTCA). METHODS AND RESULTS: Patients received a continuous infusion of either placebo or angiopeptin subcutaneously 6 to 24 hours before PTCA and for 4 days after PTCA (3 mg per 24 hours before PTCA followed by 6 mg per 24 hours after PTCA and for the remaining period). A 1.5-mg bolus dose of placebo or angiopeptin was given at PTCA. Aspirin (acetylsalicylic acid, 150 mg/d) was administered throughout the study period. Coronary angiograms obtained before and after PTCA and at 6-month follow-up were subjected to computerized quantification. Clinical follow-up was performed after 12 months. Primary clinical end points were death, myocardial infarction, coronary artery bypass surgery, or repeat PTCA. In total, 553 patients with 742 lesions were randomized. Clinical follow-up was available for all 553 patients. Angiopeptin decreased the clinical events during 12 months of follow-up from 36.4% in the placebo-treated group to 28.4% in the angiopeptin-treated patients (P = .046). Quantitative angiography after PTCA and at follow-up was available in 423 of 455 patients who underwent successful PTCA. The minimal lumen diameter at follow-up was 1.52 +/- 0.64 mm in the angiopeptin-treated group compared with 1.52 +/- 0.64 mm in the placebo-treated patients (P = .96). The late losses were 0.31 +/- 0.59 and 0.30 +/- 0.62 mm (P = .81) and the restenosis rates (> 50% diameter stenosis at follow-up) were 36% and 37% (P = .85) in the angiopeptin- and placebo-treated groups, respectively. CONCLUSIONS: In this study, angiopeptin significantly decreased the incidence of clinical events, principally the rate of revascularization procedures. In contrast, no significant effect was seen on angiographic variables.

Aged↗

PubMed1995

Randomized double-blind Scandinavian trial of angiopeptin versus placebo for the prevention of clinical events and restenosis after coronary balloon angioplasty.

Angiopeptin, a somatostatin analogue, inhibits intimal hyperplasia after percutaneous transluminal coronary artery balloon angioplasty (PTCA) in several animal models. This pilot study sought to determine the effect of subcutaneous infusion of angiopeptin on clinical events and restenosis in patients undergoing successful PTCA. One hundred twelve patients were randomized to receive continuous subcutaneous angiopeptin (750 micrograms/day) or placebo infusion from the day before PTCA and for the following 4 days in a double-blind study. An additional subcutaneous injection of 375 micrograms of angiopeptin or saline was given immediately before PTCA. Eighty patients had a successful PTCA, and 75 of these patients with 94 lesions underwent angiography 6 +/- 2 months after PTCA. All 112 patients underwent a 12-month clinical follow-up examination. Age, sex, smoking, diabetes, hypertension, hyperlipidemia, and morphologic features of stenosis were similar in both groups. The hierarchical 12-month event rate (death, myocardial infarction, coronary artery bypass grafting, and repeated PTCA) was reduced from 34% to 25% (p = 0.30) by angiopeptin by intention-to-treat analysis. Restenosis (> or = 50% diameter stenosis) was significantly reduced in lesions treated with angiopeptin (12% vs 40%; p = 0.003). Late lumen loss also was significantly reduced after angiopeptin treatment (0.12 +/- 0.46 mm vs 0.52 +/- 0.64 mm; p = 0.003). In conclusion, continuous subcutaneous angiopeptin infusion for 5 days tended to decrease clinical events and restenosis after PTCA.

Angioplasty, Balloon, Coronary↗

PubMed1995

Upper endoscopy in patients with angina and normal coronary angiograms.

BACKGROUND AND STUDY AIMS: It has been recommended that patients with angina, a normal coronary angiogram, and no other signs of heart disease, should be evaluated using esophagogastroduodenoscopy before referral to dynamic esophageal investigations. The aim of the present study was to investigate the clinical value of upper endoscopy in this patient group. PATIENTS AND METHODS: Forty-nine consecutive patients (28 women aged 18-70 years, mean 51.6 years) with angina-like chest pain and a normal coronary angiogram, who were referred to a tertiary cardiologic center, were included in a prospective study. Upper endoscopy with distal esophageal biopsies was performed. The results were compared with 24-hour pH monitoring. At a median of 36 months after discharge, the patients were asked to complete a follow-up questionnaire. RESULTS: Macroscopic esophagitis was found in 15 patients (31%), and microscopic esophagitis in 11 (25% of the patients who underwent esophageal biopsy). One patient had macroscopic grade II esophagitis, and the rest had grade I esophagitis. The only major abnormalities were three peptic ulcers (6%). Five patients had symptoms of gastroesophageal reflux, but the 24-hour pH monitoring revealed an abnormal reflux index in only one. The median reflux index was 1.3 (range 0.0-13.4) in the patient group and 2.1 (range 0.0-9.9) in a control group (n = 22; p = 0.49). Patients with positive and normal exercise electrocardiography did not differ in terms of the endoscopic findings or reflux index. At the post-study follow-up, 38% of the patients had undergone acid secretion inhibitor treatment, with an effect on symptoms in only 4%. CONCLUSIONS: The study provides evidence that routine esophagogastroduodenoscopy is of limited value in this group of patients.

Adolescent↗

PubMed1995

Persistent atrial fibrillation following electrical injury.

Supraventricular arrhythmias are seen following non-fatal electrical injuries. They are believed to be transient, but this has never been confirmed. We report a case of fixed atrial fibrillation that has persisted for 20 years after an electrical injury at work.

Accidents, Occupational↗

PubMed1995

Autonomic balance in patients with angina and a normal coronary angiogram.

The pathophysiology of angina pectoris in patients with a normal coronary angiogram is not clear. Furthermore, the pathophysiological impact of ST changes in syndrome X is controversial. The purpose of this study was to investigate cardiac autonomic function, by measuring 24 h heart rate variability, in patients with and without electrocardiographic evidence of ischaemia during exercise. Thirty-two patients with angina pectoris, a normal coronary angiogram, echocardiogram, hyperventilation test and gastro-oesophageal investigation were studied. Fourteen healthy subjects served as controls. Fifteen patients had significant ST segment depression during stress testing, whereas 17 had no electrocardiographic signs of ischaemia. Heart rate variability was calculated as (1) mean RR = mean of all normal RR intervals, (2) the difference in mean RR level between when awake and when asleep (mean RR wake-sleep)-a tentative index of sympathetic activation, (3) the standard deviation (SD)-a broad band measure of autonomic balance, and (4) a percentage of successive RR interval differences > or = 6% (pNN6%)-an index of vagal modulation. The coronary vascular resistance was measured at rest and during pacing. Mean RR and autonomic indexes did not differ between patients with a positive exercise test and controls (831/884 ms; 24 h SD 125/134 ms; pNN6% 6.715.4%, respectively). Patients with a normal exercise test had shorter mean RR (758 ms vs 844 ms; P < 0.05) and significantly reduced 24-h SD (103 ms vs 134 ms; P < 0.05) than controls, whereas values for vagal index (6.5% vs 5.4%) did not differ from healthy controls. Mean RR wake-sleep also tended to be lower in patients with a normal exercise test (-125 ms vs -173 ms) compared to controls (P < 0.1). Patients with a positive exercise test had a significantly attenuated reduction in coronary vascular resistance during pacing in comparison to patients with a normal exercise test (-0.131 -0.26 mmHg x min. ml-1; P < 0.05). The findings suggest the occurrence of general elevated sympathetic activation in angina patients with a normal exercise test. Patients with a positive exercise test exhibited no signs of autonomic dysfunction although these patients had altered coronary vascular resistance indicating microvascular angina. This supports the suggestion that patients with a normal exercise test constitute an independent pathophysiological entity.

Adult↗

PubMed1995

Oesophageal sensation assessed by electrical stimuli and brain evoked potentials--a new model for visceral nociception.

Sensory thresholds and brain evoked potentials were determined in 12 healthy volunteers using electrical stimulation of the oesophagus 28 and 38 cm from the nares. The peaks of the evoked potentials were designated N for negative deflections and P for positive. Continuous electrical stimulation (40 Hz) at the 38 cm position resembled heartburn (five of 12 subjects) while non-specific ('electrical') sensations were provoked at 28 cm (10 of 12). Thresholds of sensation and of pain were lower at the initial than the second determination, but did not differ with respect to stimulation site. The pain summation threshold to repeated stimuli (2 Hz, 5 stimuli) was determined for the first time in a viscus. This threshold was lower than the pain threshold to single stimuli at 38 cm (p < 0.02). Evoked potential latencies did not change significantly over a six month period while the N1/P2 amplitude was higher at the first measurement (p < 0.05). P1 and N1 latencies were significantly shorter 38 cm (medians 100 and 141 ms) than 28 cm from the nares (102 and 148 ms) (p = 0.04 and p = 0.008). Electrical stimulation of the oesophagus may serve as a human experimental model for visceral pain. Longer evoked potential latencies from the proximal compared with distal stimulations provide new information about the sensory pathways of the oesophagus.

Adult↗

PubMed1995

Somatostatin enhances insulin-stimulated glucose uptake in the perfused human forearm.

Somatostatin is widely used in experimental metabolic studies to control hormone actions. It has also been suggested that, in addition to its well known suppressive effects, somatostatin per se may increase insulin sensitivity. In order to examine this suggestion, we gave six healthy male volunteers (age 33 +/- 1 yr, mean +/- SEM; body mass index, 24.1 +/- 0.6 kg/m2) either a local intraarterial (brachial artery) or a systemic venous infusion of 25 micrograms/h somatostatin twice. The study consisted of a 1-h basal period and a 2-h systemic hyperinsulinemic (0.4 mU/kg.min) euglycemic clamp. Compared with the systemic control infusion, local forearm perfusion with somatostatin caused a 55% increase in insulin-stimulated forearm glucose uptake (0.74 +/- 0.18 vs. 0.47 +/- 0.19 mmol/L, P < 0.05). Intraarterial somatostatin perfusion did not alter basal forearm glucose uptake (0.14 +/- 0.07 vs. 0.17 +/- 0.12 mmol/L), the amount of glucose administered during the clamp (M-value, 3.2 +/- 0.5 vs. 3.0 +/- 0.6 mg/kg.min), or the levels of insulin, C-peptide, glucagon, or GH. Intermediary metabolite exchange across the forearm, total forearm blood flow, and oxygen saturations also remained stable. Glucose concentrations were slightly higher (0.06 +/- 0.01 mmol/L) in arterial than in arterialized blood, whereas lactate concentrations were comparatively decreased (108 +/- 51 mumol/L) in arterial blood. Our data suggest that somatostatin increases insulin-stimulated muscle utilization of glucose through local mechanisms. Although the nature of this increase remains to be established, it should be taken into consideration in metabolic studies using somatostatin.

3-Hydroxybutyric Acid↗

PubMed1994

Prospective randomised trial of atrial versus ventricular pacing in sick-sinus syndrome.

In patients with sick-sinus syndrome, single-chamber atrial pacing has been reported, in retrospective studies, to be associated with lower frequencies of atrial fibrillation, thromboembolism, heart failure, and mortality than ventricular pacing; although single-chamber ventricular pacing is most commonly used. We did a prospective randomised trial in 225 consecutive patients (142 women, 83 men; mean age 76 years) with the sick-sinus syndrome, randomised to atrial (n = 110) or ventricular (n = 115) pacing and followed for up to 5 years (mean 40 [SD 18] months). During follow-up, the frequency of atrial fibrillation was higher in the ventricular group, except at the first follow-up at 3 months. Thromboembolic events (stroke or peripheral arterial embolus) occurred in 20 patients in the ventricular group and in 6 patients in the atrial group (p = 0.0083). 25 patients died in the ventricular group compared with 21 in the atrial group (p = 0.74). Heart failure estimated by the New York Heart Association classification and by the daily doses of diuretics did not differ between the two groups. Atrioventricular block occurred in 2 patients in the atrial group. Patients with sick-sinus syndrome should be treated with atrial pacing rather than ventricular pacing because atrial pacing is associated with lower frequencies of atrial fibrillation, thromboembolic complications, and a low risk of atrioventricular block.

Aged↗

PubMed1994

Electric stimulation of the esophageal mucosa. Perception and brain-evoked potentials.

BACKGROUND: Brain potentials have been used to assess somatosensory, visual, and auditory function, whereas few attempts have been made to evoke brain potentials from viscera. METHODS: The present study evaluated perception and brain potentials evoked by electric stimulation at four different intensities in the esophagus of healthy volunteers. Results were compared with somatosensory evoked potential variables. RESULTS: In 6 of 10 subjects the two highest esophageal stimulus intensities caused a deep pain perception. A positive correlation between average esophageal stimulus intensity and age was demonstrated. The amplitude of brain potentials increased significantly as a function of both esophageal and cutaneous stimulus intensity. The latency of esophageally evoked potentials decreased with stimulus intensity and was substantially longer than cutaneously evoked potentials despite a comparable conduction distance. CONCLUSIONS: The present methods provide possibilities to assess sensory mechanisms and perception related to the human esophagus.

Adult↗

PubMed1993

Insulin resistance in microvascular angina (syndrome X)

Patients with microvascular angina (syndrome X) may be insulin resistant. We designed a study to establish whether this is the case. 11 patients with microvascular angina were compared with 9 matched subjects with noncardiac chest pain. Patients and controls were evaluated by coronary sinus catheterisation, and by isotopic measurement of glucose turnover, indirect calorimetry, and forearm technique during a 3 h baseline period after overnight fast and during a 2 h hyperinsulinaemic euglycaemic clamp. Pace-induced increase in coronary sinus blood flow was less in patients than in controls, whereas forearm blood flow did not differ between groups. Baseline measures of glucose metabolism were normal. During the clamp, glucose production and lipolysis were equally suppressed in both groups. Mean (SE) total insulin-induced glucose uptake was significantly impaired in patients compared with controls (3.9 [0.7] vs 6.4 [0.7] mg/kg per min; p < 0.01), and insulin-stimulated glucose uptake in the forearm was significantly reduced in patients (0.88 [0.10] vs 1.6 [0.30] mmol/L; p < 0.001). Reduced oxidative and nonoxidative metabolism accounted for the defect in overall glucose uptake in patients. No correlation between changes in coronary sinus blood flow and total body glucose uptake was seen. We found that microvascular angina was associated with substantial insulin resistance. Whether this relation is causal or coincidental is as yet unsettled.

Alanine↗