Noninvasive monitoring of rejection therapy based on intramyocardial electrograms after orthotopic heart transplantation. Initial experience with 14 cases.

Despite the use of increasingly specific immunosuppressive therapy, rejection remains the leading cause of death in cardiac transplant patients. Endomyocardial biopsy (EMB) is the gold standard for early detection and monitoring of cardiac transplant rejection. However, this approach is invasive and not suitable for routine use. A noninvasive alternative for monitoring cardiac transplant patients uses the analysis of the ventricular evoked response (VER) obtained by programmed electrical stimulation. Rejection-sensitive parameters (RSP) and infection-specific parameters (ISP) are extracted from changes in the slope of the T-wave and from the duration of repolarization, respectively. For the analysis of intramyocardial electrograms, separate left and right ventricular pacing at a rate of 100 beats/min and lasting 60 s is required, following the same protocol. From year 2000, telemetric pacemakers were implanted in 14 patients undergoing heart transplantation at this institution. A total of 95 endomyocardial biopsies and 275 ventricular evoked response measurements were carried out. Five out of 6 cases with significant rejection were correctly identified by RSP values below a threshold of 98% (sensitivity=80%, specificity=50%, negative predictive value=97%, positive predictive value=11%; P<0.002). Of the EMBs, 45% could have been saved if the diagnosis model had been used to indicate need for EMB. Noninvasive cardiac graft monitoring can reduce the need for surveillance biopsies and may offer a tool to optimize immunosupressive therapy after heart transplantation. Rejection grade 2 or higher can safely be detected.

Late complications and shape changes of the endografts after gigantic thoracic aortic aneurysm repair over a 7-year follow-up.

This report details a 7 years follow up observations in a 71-year-old patient treated with custom made endograft for gigantic thoracic aortic aneurysm (TAA). Progressive changes of the thoracic aorta and aneurysm after endograft placement led to two late complications including proximal stent graft prolapse into the aneurysm and extreme kinking of the endograft and aorta 28 and 51 months after treatment, respectively. Both complications were successfully treated with new endografts placement. Percutaneous endovascular repair is a promising, minimally invasive alternative to exclude TAA. This technique allows long-term treatment of patients who are unsuitable for conventional surgical procedures.

Results of treatment of 17 patients with heart tumour.

BACKGROUND: Between 1989 and 1997, 17 patients underwent surgery for excision of primary cardiac tumour at the Department for Cardiovascular Surgery in Ljubljana. PATIENTS AND METHODS: There were 13 female (76.5%) and four male (23.5%) patients with an average age of 49+/-14 years (mean+/-SD). The study was retrospective. Special attention was paid to clinical presentation, method of diagnosis, elapsed time between the confirmed diagnosis and excision of the tumour, operatively determined location of tumour and post-operative course-diuresis in first 48 h, levels of CK and CK-MB, on first and on second day after operation and time of hospitalization. RESULTS: Thirteen patients (76.5%) had cardiac symptoms at the time of presentation (dyspnoea, syncope, vertigo, palpitations) and four (23. 5%) had embolic complications. In all the patients diagnosis was made by echocardiography. Average elapsed time between the confirmed diagnosis and the operation was 26+/-40 (mean+/-SD) days. Histological examination revealed myxoma in 15 patients (88.2%), one patient had lipoma and one malignant haemangiosarcoma. The most common location of tumour was in the left atrium (12 patients; 70. 6%). Post-operative complications occurred in four patients (23.5%); 76.5% of patients had diuresis in the range between 0.8 and 2.0 ml/h/kg; there was no post-operative oligouric renal failure. Average levels of both CK and CK-MB were statistically significantly lower on the second day after operation, there was no case of peri-operative myocardial infarction and post-operative death did not occur. One patient with multiple myxoma had two recurrences. CONCLUSIONS: Symptoms in patients with heart tumours, especially at the beginning of illness, are often uncharacteristic. Due to the non-specific presentation of cardiac tumours, a high index of suspicion is needed. The diagnostic method of choice is echocardiography. Operative removal of tumour is a safe procedure and recurrences in patients with benign tumours are rare.

Computer simulation and spatial modelling in heart surgery.

In this work, three dimensional modelling and computer simulation of heat transfer on generally-shaped nonhomogeneous bodies is proposed and described. The complexity of the calculation is estimated and the potential use of high performance parallel computers is discussed. The method is focused on applications in medicine. As an example, a numerical algorithm for the parallel computer simulation of heart cooling procedures during surgery is presented. On the basis of simulated results, two different methods of cooling are compared.

[Successful surgical revascularization after 18 hour ischemia below the knee due to complete avulsion of the popliteal artery]. / Erfolgreiche chirurgische Revaskularisation nach 18stündiger Ischämie unterhalb des Knies infolge eines vollständigen Abrisses der A. poplitea.

We report the case of a 33-year-old man after knee luxation and disruption of a popliteal artery, which was missed after repositioning at the first clinic. Eighteen hours later complete discontinuity of the popliteal artery was confirmed by arteriography and an immediate reversed, end-to-end auto-venous graft was interposed under general anesthesia with anterior and posterior fasciotomy prior to blood flow restoration. Forced diuresis with a diuretic mixture and balanced fluid intake were used, and the patient was discharged from the intensive care unit on the 10th postoperative day in good condition with normal diuresis.

Transfemoral intraluminal stent graft implanted for thoracic aortic aneurysm.

We describe two patients with inoperable descending thoracic aortic aneurysm. The first patient had complained of severe back pain for at least thirteen years. Radiological examination revealed a large posterior mediastinal mass that was misdiagnosed in 1981. Follow-up studies in 1992 revealed this mass to be a large descending thoracic aortic aneurysm, eroding the vertebral bodies of T3 through T6 and entering the spinal canal. Because of the high risk, thoracic aortic surgery was not performed. The second patient had an acute descending thoracic aortic aneurysm. There was contraindication to a second surgical approach due to previous thoracotomy. Both patients underwent an intraluminal bypass of the descending thoracic aorta with a stent graft. Postplacement aortogram and follow-up studies showed that aneurysm was effectively excluded. We believe that this type of therapy should be offered to selected individuals who are considered by cardiovascular surgeons to be a high risk for thoracic aneurysm surgery.

Successful surgical removal of partially expanded Palmaz stent from external iliac artery.

Insertion of intravascular stents into various arteries including coronary arteries has become an integral part of vascular interventions, particularly in the treatment of aortoiliac arteriosclerotic disease. The incidence of vascular complications remains relatively high despite the better stent design and inserting techniques. We report a case where successful removal of partially expanded Palmaz stent from external iliac artery was needed due to a rare complication: a balloon catheter burst resulting in an insufficient stent expansion in an improper position.