Search PubMed⌕ Search

Biomedical subjects

B Ibrahim

Publications and source records attributed to B Ibrahim.

25 records · Page 2Linked to original sources

Combined time-domain and spectral turbulence analysis of the signal-averaged ECG improves its predictive accuracy in postinfarction patients.

The predictive accuracy of time-domain (TD) late potential analysis of the signal-averaged electrocardiogram in postmyocardial infarction (MI) is limited by the high incidence of false positives in inferior MI. However, frequency-domain spectral turbulence (ST) analysis suffers from a high incidence of false positives, especially in anterior MI. A prospective study was conducted of 262 patients with acute MI to investigate the hypothesis that combined TD and ST analyses of the signal-averaged electrocardiogram could improve its predictive accuracy for serious arrhythmic events in the post-MI period. Abnormal TD criteria were RMS40 less than 25 microV at 25 Hz plus RMS40 less than 16 microV at 40 Hz, and abnormal ST criteria were a turbulence score of 3 or 4. Seventeen patients had arrhythmic events during 10.5 +/- 2.4 months of follow-up evaluation (13 sudden cardiac death judged to be due to arrhythmia and 4 nonfatal sustained ventricular tachycardia). The total predictive accuracy of combined TD and ST (92%) was higher than TD (87%), whereas ST had the lowest total predictive accuracy of 78%. The negative predictive accuracy of all three analyses was high (96-97%). However, the positive predictive accuracy of TD (28%) was higher than ST (14%). Combined TD and ST significantly improved the positive predictive accuracy of the test to 35% in the total group and to 40% in patients with first anterior or inferior MI. The best results were obtained in patients with first anterior MI, where the positive predictive accuracy of combined analysis was 50%.

Arrhythmias, Cardiac↗

Spinal electrical stimulation for intractable angina--long-term clinical outcome and safety.

Spinal cord electrical stimulation is an alternative therapy for patients with chronic pain syndromes including angina. Although it has been shown to produce symptomatic relief and reduce ischaemia, doubts remain about its long-term safety. We report here for the first time the results of a follow-up study over a period of 62 months, mean 45 months (range 21-62), of 23 patients who had stimulator units implanted for intractable angina unresponsive to standard therapy. Symptomatic improvement was good and persisted in the majority with a mean (SD) change of NYHA grade from 3.1 (0.8) pre-operatively to 2.0 (0.9) (P < 0.01) immediately after operation and 2.1 (1.07) at the latest follow-up. GTN consumption fell markedly. Mean (SEM) treadmill exercise time increased from 407 (45) s with the stimulator off to 499 (46) s with the stimulator on (P < 0.01). Forty-eight hour ST segment monitoring in those with bipolar leads showed a reduction of total number and duration of ischaemic episodes. There were three deaths, none of which were sudden or unexplained and this mortality rate is acceptable for such a group of patients. Two patients had a myocardial infarction, which was associated with typical pain and not masked by the treatment. Complications related to earlier lead designs were frequent. This study confirms that spinal electrical stimulation is an effective and safe form of alternative therapy for the occasional patient whose angina is unresponsive to standard therapies.

Angina Pectoris↗

Internal mammary artery angiography should be a routine component of diagnostic coronary angiography.

Left internal mammary artery (LIMA) angiography was performed with diagnostic coronary angiography in 130 cases for which the coronary findings made use of the LIMA as a bypass graft a consideration. In 98% of the cases the approach to LIMA angiography was femoral with a 5F LIMA catheter first directed into the proximal subclavian and then advanced over a guidewire placed into the distal subclavian well beyond the origin of the LIMA. After withdrawing the wire the catheter was brought proximally to selectively cannulate and visualize the LIMA with nonionic contrast media. The only complication was a single transient occipital visual field loss. LIMA caliber too narrow to permit use as a graft was found twice, LIMA occlusion unrelated to prior surgery was found once, and LIMA occlusion related to prior surgery was found twice. Subclavian and/or vertebral stenosis was present five times. Large proximal branches of the LIMA best identified prior to surgery were present 12 times. Based on this experience, LIMA angiography 1) can be performed safely with a high degree of success, 2) demonstrates significant findings in 15% of cases, and 3) should therefore be performed whenever coronary angiographic findings make it appropriate to consider LIMA to coronary artery bypass grafting.

Adult↗

Learning disabilities among Nairobi school children.

Four hundred and forty-one school children studying in local primary schools were referred during 1980-1981 to the Psychological Assessment Clinic in Nairobi (Kenya) for poor academic performance. The most frequent cause for the learning difficulties of these children was mental retardation. In one third, emotional disorders were responsible for their learning difficulties. Currently, even mentally retarded children are admitted into the existing educational system and are unable to cope. Recommendations for the future are made.

Adolescent↗