SUMMARY An electrocardiographic atlas of ventricular tachycardias was produced by pacing 27 epicardial sections of the heart and the mitral papillary muscles to simulate focal ventricular arrhythmias and simultaneously recording their 12 lead electrocardiographic appearances. One hundred and twenty nine patients undergoing cardiac surgery were studied. In five patients all 27 epicardial sites were paced at operation and in 124 individual sections were paced postoperatively with temporary epicardial wires and the electrocardiograms analysed in terms of frontal and horizontal plan QRS axis, maximum limb lead QRS amplitude, and QRS duration. Each ventricular region paced produced a distinctive 12 lead electrocardiographic pattern.Simulated right ventricular arrhythmias had either inferior frontal plane QRS axes (from the anterobasal region) or superior frontal plane QRS axes (from the apical and posterior right ventricular sections). Horizontal plane QRS axes were directed leftwards, with some posterior shift in the anteroapical regions. Simulated arrhythmias from the base of the left ventricle (anteriorly and laterally) had inferior frontal plane QRS axes and anterorightward horizontal plane QRS axes. Left ventricular arrhythmias with a superior frontal plane QRS axis were readily distinguished by their horizontal plane QRS axes: posterorightwards from the anterior and anterorightwards from the posterior left ventricular sections. Standard errors of the paced QRS axes for the various epicardial sections paced postoperatively ranged from 3-00 to 6.00 using the frontal plane axis. The electrocardiogram was most accurate in localising ventricular arrhythmias from the anterior left ventricle and least accurate for those arising from the inferior right ventricle. The appearance of the paced electrocardiograms was slightly modified by underlying disease such as myocardial infarction and left ventricular hypertrophy.This atlas may be useful in comparing the localisation of ventricular tachycardia with the site of underlying cardiac disease and may facilitate mapping in patients with refractory ventricular tachycardia requiring ablation (either surgical or by high energy impulses).

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Near infrared spectroscopy (NIRS) is a relatively new method which is suitable for monitoring oxygenation in blood and tissue in the brain of the fetus and the neonate. The technique involves in vivo determination of the absorption of light in the wavelength range 775 to 900nm through such tissue and converting such changes in absorbance to provide information about the changes in the concentration of oxygenated and de-oxygenated haemoglobin (Hb02 and Hb). Recent developments of the methodology now enable the calculation of changes in cerebral blood volume (CBV) as well as absolute CBV and cerebral blood flow (CBF). The attraction of this method is it's applicability to monitor cerebral function in wide variety of patient groups. Although primarily developed for neontal use it is today applied on the fetus to investigate fetal hypoxia and on adults undergoing surgery.

Coronary artery bypass surgery with or without aneurysmectomy is used to treat patients with left ventricular aneurysm. There is debate about patient selection and the appropriate surgical technique. We analyzed the results of 102 consecutive patients who underwent left ventricular aneurysmectomy and reconstruction using a modified linear closure technique between 1992 and 2003. The mean age was 62 years, 81% of the patients were male, and 47% had an ejection fraction < 35%. The locations of the left ventricular aneurysms were anteroapical (75%), apical (21%), and posteroinferior (4%); 23% contained thrombi. Additional procedures included aortic valve replacement in 4, mitral valve repair in 1, and coronary bypass grafting in 98 patients; 3 underwent isolated repair of left ventricular aneurysm. Hospital mortality was 7% and long-term survival was 76% at a mean follow-up of 39 months. Most patients improved symptomatically postoperatively. Left ventricular aneurysm repair with tailored scar excision and a modified closure technique is associated with acceptable mortality and long-term survival.