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Fourteen relatively long term survivors of cardiac transplantation underwent systematic electrophysiological evaluation and ambulatory electrocardiographic monitoring. Six patients had prolonged conduction intervals during sinus rhythm. Sinus node function could be assessed in all donor atria and in 10 recipient atria. Sinus node recovery times were prolonged in four of the donor atria and in six recipient atria. In the donor atria abnormalities of sinus node automaticity were invariably associated with abnormalities of sinoatrial conduction. Four patients showed functional duality of atrioventricular nodal conduction during programmed extrastimulation, but no patient developed re-entrant arrhythmia. During ambulatory electrocardiographic monitoring no pronounced tachyarrhythmias were recorded. Three patients showed abnormalities of sinus node impulse formation. All three patients had abnormal sinus node recovery times during their electrophysiological study. Long term survivors of cardiac transplantation have a high incidence of electrophysiological abnormalities. Abnormalities of donor sinus node function are probably of clinical significance. The clinical significance of abnormalities detected within the atrioventricular conduction system of the denervated heart remains to be elucidated. [ABSTRACT FROM PUBLISHER]

Six cardiac transplant recipients underwent maximal exercise testing before and after the administration of intravenous propranolol to assess the effect of beta blockade on their exercise heart rate response and exercise capacity. Before propranolol the patients were capable of a mean of 6.8 minutes of exercise and heart rate increased from a resting value of 102 +/- 25 a minute to 138 +/- 34 at peak exercise--a mean increase of 35%. All tests were terminated because of tiredness or muscle weakness. After one hour's rest, intravenous propranolol (0.2 mg/kg over 10 minutes) was administered with a reduction in resting heart rate from 109 +/- 28 a minute to 83 +/- 16. During the repeat exercise test the patients were capable of a mean of 4.5 minutes of exercise and all tests were terminated by extreme exhaustion and/or unsteadiness requiring immediate cessation of the treadmill. Heart rate increased from a resting value of 83 +/- 16 a minute to 96 +/- 18 at peak exercise. The exercise capability of the denervated heart is conspicuously reduced by beta blockade, presumably because of its reliance on circulating catecholamines. [ABSTRACT FROM PUBLISHER]

A raised hemidiaphragm has been reported as an uncommon complication of cardiopulmonary bypass, possibly resulting from cold injury to the phrenic nerve. At Papworth Hospital myocardial protection during cardiac arrest relies in part on irrigation of the pericardial cavity with large volumes of Hartmann's solution at 4 degrees C. Retrospective review of the chest radiographs of 100 consecutive patients undergoing cardiopulmonary bypass showed that 31 had a raised left hemidiaphragm soon after operation. The only significant correlation was with aortic cross clamp time (p less than 0.03). A prospective study of 36 consecutive patients undergoing cardiopulmonary bypass was then undertaken with diaphragmatic screening and chest radiography. Preoperative screening gave normal results in all patients. In the early postoperative period 16 (44%) had left diaphragmatic weakness or paralysis, two (5.5%) right sided weakness, and two (5.5%) bilateral weakness. Repeat screening of these patients showed resolution in all but four cases (80%) at six months and in all but two (90%) at one year. The greater number of left sided lesions than of right (8:1) is probably due to the fact that the cold jet of irrigating fluid is directed towards the left phrenic nerve. These findings have implications with regard to the optimum temperature of the irrigant fluid for myocardial protection during cardiopulmonary bypass. [ABSTRACT FROM AUTHOR]

The first case of disseminated toxoplasmosis following cardiac transplantation in the UK is described, with details of Toxoplasma antibody tests made on other cardiac transplant patients. Sixteen of 40 (39%) of recipients had Toxoplasma antibody before operation. Eleven of 30 (37%) of donors had Toxoplasma antibody. The were four occasions when a negative recipient received a heart from a positive donor. Three survived the immediate postoperative period and two became infected with toxoplasmosis. The implications of this are discussed. Disseminated toxoplasmosis appears much more often when heart muscle from a dye test positive donor is given to a dye test negative recipient. Antibiotic therapy is limited by the fact that the antitoxoplasma drugs available are static in their effect, and need to be given for prolonged periods postoperatively. [ABSTRACT FROM PUBLISHER]

Donor sinus node function was studied in 10 patients from day 4 to day 24 after cardiac transplantation. Cycle length, atrial arrhythmias, corrected sinus node recovery time, and estimated sinoatrial conduction time were recorded daily. Five patients had at least two sets of results suggesting sinus node dysfunction (group A) while five patients had no such abnormalities (group B). The prognosis in group A was poor, with four of the five patients dying within four months of the operation; one unexpected death from arrhythmias was recorded by ambulatory electrocardiographic monitoring. All five patients in group B survived for at least eight months. In nine patients sinus node function varied from day to day, with corrected sinus node recovery time reaching a peak at 11 to 18 days after operation. The longest corrected sinus node recovery time was 11 160 ms. Neither the differences between the patients, nor the day to day variation, could be explained solely by the degree of rejection as assessed by biopsy or by the ischaemia time of the heart during procurement. Sinus node dysfunction soon after transplantation is associated with a poorer prognosis and might be the terminal event in some cases. [ABSTRACT FROM PUBLISHER]

A 74 year old woman with mixed mitral valve disease presented with episodes of loss of consciousness and fainting. The attacks were noted to be closely related to posture, especially crouching, and this, with the clinical finding that the radial pulse disappeared before she lost consciousness, suggested the diagnosis of a ball valve thrombus. Cardiac catheterisation confirmed the diagnosis but was followed by a fall in blood pressure necessitating emergency surgery. The only position in which the circulation could be maintained was the right lateral, with steep head down tilt, and left femoro-femoral cardiopulmonary bypass had to be established in this position. Operation confirmed the presence of a ball valve thrombus and the patient recovered uneventfully. [ABSTRACT FROM PUBLISHER]

A fatal early acute rejection occurred in a heart allograft recipient immunosuppressed with Cyclosporine. This failure to prevent rejection in spite of satisfactory plasma levels of Cyclosporine was associated with total absence of renal impairment. The latter has always been present in our experience. The absence of immune and nephrotoxic effects raises the question of a biological defect in this patient, possibly a lack of specific receptors for Cyclosporine.

The function of both the denervated donor and innervated recipient sinus nodes of 14 asymptomatic cardiac transplant recipients was assessed. Tests of sinoatrial function were performed in 14 donor and 10 recipient atria. The mean spontaneous cycle length of the recipient atria was significantly longer than that of the donor atria (944 +/- 246 versus 663 +/- 158 ms, p less than 0.01). Donor sinus node recovery time was prolonged in four patients (greater than 2,500 ms in two) and recipient recovery time was prolonged in six patients. In those patients with normal sinus node function tests, the recovery time of the recipient sinus node was longer than that of the donor sinus node (1,170 +/- 207 versus 864 +/- 175 ms, p less than 0.02). The pattern of response of recovery times to increasing pacing rate was predictable and organized in the donor but chaotic in the recipient, and the longest sinus node recovery time occurred at the shortest pacing cycle length used in 12 of the 14 donor atria but in only 1 of the 10 recipient atria (p less than 0.001). Secondary pauses occurred in none of the normal donor atria and in all of the abnormal donor atria (p less than 0.001); however, they occurred in both normal and abnormal recipient atria. The recipient and donor atria were paced alone and synchronously in the same patients. Synchronous pacing had no effect on the recovery times of the donor sinus node but significantly lengthened those of the recipient (sinus node recovery time: 1,266 +/- 218 to 1,547 +/- 332 ms, p less than 0.02; corrected recovery time: 322 +/- 102 to 686 +/- 188 ms, p less than 0.01). In the donor atria, abnormal recovery time was invariably associated with abnormal sinoatrial conduction time. There was a strong correlation between sinoatrial conduction time measured by the methods of Strauss and Narula and their coworkers in the donor atria (r = 0.98, p less than 0.001) but not in the recipient atria (r = 0.72). In the absence of autonomic influences, tests of sinus node function of the donor atria produce predictable and consistent results and, therefore, may be more clinically reliable than in intact human subjects. There is a high incidence of recipient sinus node dysfunction in asymptomatic long-term survivors of cardiac transplantation.

It is usual to record independent activity from both the innervated recipient and the denervated donor atria in cardiac transplant recipients except for occasional, short-lived periods of entrainment that may occur during exercise. In this report a case is described in which, following orthotopic cardiac transplantation, the recipient and donor atria remained synchronized during a variety of physiological and non-physiological situations. Under no circumstances did the two sets of atria beat independently. The mechanisms that might be involved in this unique situation are discussed.

The incidence of keloid and hypertrophic change and of scar stretching in the presternal region were studied in a fair-skinned population following open heart surgery through a median sternotomy incision. No patient in this study developed keloid change although scar hypertrophy and stretching were frequent. These changes were unrelated to the material used in subcuticular suture of the skin in a comparison of catgut, prolene and polyglycolic acid. Hitherto, unrecognised differences of scar maturation between different areas of the presternal skin were noted to be statistically significant. Scar hypertrophy is most likely in that part of the scar overlying the body of the sternum and particularly in the female. Scar stretching occurs most frequently in the lower third of the scar overlying the xiphisternum and extending onto the abdomen.

A 13 year old girl with Ebstein's anomaly was investigated for refractory paroxysmal tachycardias and ventricular pre-excitation. Intracardiac electrophysiological studies demonstrated that ventricular pre-excitation was due to conduction in an anomalous nodo-ventricular pathway. Tachycardia occurred as a result of re-entry within the A-V node with pre-excitation during tachycardia due to conduction in the nodo-ventricular pathway. These tachycardias were controlled initially by medical therapy but because of increasing frequency of attacks, occasionally requiring D.C. conversion, further electrophysiological studies and epicardial mapping were undertaken. The epicardial surface of the right ventricle and right atrium were mapped during tachycardia. The results of the studies confirmed that a direct anomalous atrio-ventricular pathway was not present and that re-entrant tachycardia did not involve an accessory pathway of this type. A rapid atrial pacing system was implanted and paroxysmal tachycardias have been successfully controlled.

Infectious complications constitute a major cause of morbidity and mortality after heart transplantation. Those infections transmitted with the transplanted heart are potentially avoidable. Cytomegalovirus infections and toxoplasmosis occupy a prominent position in this category. The outcome of transplanting hearts from donors previously exposed to these infections depends largely on the existing immune status of the recipient. This paper is a retrospective study on the incidence of Toxoplasma gondii and cytomegalovirus infections in patients undergoing heart and heart-lung transplantation at Papworth Hospital, Cambridge.

The electrophysiologic characteristics of the denervated human heart were assessed in 14 cardiac transplant recipients. Conduction intervals and refractory periods were measured at pacing cycle lengths of 500 msec and 400 msec. The faster pacing rate caused lengthening of the AH interval (83 +/- 23 msec to 116 +/- 41 msec, p less than 0.01) and shortening of the QT (338 +/- 27 msec to 313 +/- 22 msec, p less than 0.001) and JT (249 +/- 21 msec to 229 +/- 19 msec, p less than 0.001) intervals. There was no change in the SA, HV, or QRS durations. Wenckebach periodicity occurred at a longer cycle length in the retrograde than in the anterograde direction (409 +/- 96 msec vs 318 +/- 46 msec, p less than 0.01) and anterograde conduction was better than retrograde conduction in 13 of the 14 patients (93%). Increasing pacing cycle length resulted in shortening of the atrial effective (203 +/- 28 msec to 190 +/- 25 msec, p less than 0.001), ventricular effective (224 +/- 18 msec to 211 +/- 17 msec, p less than 0.01), and AV nodal functional (367 +/- 38 msec to 357 +/- 36 msec, NS) refractory periods. The AV nodal effective refractory period lengthened (294 +/- 31 msec to 314 +/- 52 msec, p less than 0.05). There was a close correlation between AV Wenckebach cycle length and the functional refractory period of the AV node (r = 0.853, p less than 0.001). These results are qualitatively and quantitatively similar to those reported in the innervated heart. The autonomic nervous system appears to have little influence on the resting electrophysiologic characteristics of the atrioventricular conduction system in the innervated heart.