Bartonella quintana endocarditis of the tricuspid and mitral valves

Bartonella quintana is a gram-negative microorganism that can lead to culture-negative infective endocarditis (IE) in immunocompromised patients. Here, we present an exceptionally rare case of a 70-year-old male with Bartonella quintana-associated IE primarily limited to the tricuspid valve that spread to the mitral valve after tricuspid valve replacement. This was then complicated by infective spondylodiscitis of the thoracic vertebrae, ultimately resulting in death due to cardiac arrest.

Cell sources for cardiovascular tissue regeneration and engineering

The heart has long been regarded as a post-mitotic organ. Since many years, physicians have focused on developing strategies to restore the myocardium after ischemic damage followed by ventricular dysfunction. Restoration is generally achieved through the redirection of blood flow or by supporting contractile performance. The discovery of stem cells capable of generating angiogenic or contractile cells and structures offers new horizons to patients suffering from myocardial disease. Experimental studies indicate that the delivery or mobilization of stem and progenitor cells may improve tissue perfusion and the contractile performance of the damaged heart. Another aspect of restoration is based on cardiovascular tissue engineering and the creation of three-dimensional biological conformations to replace the artificial materials frequently used during operations, i.e., valves and grafts, or even a portion of the nonfunctional myocardial tissue. At present, the underlying intra- and intercellular molecular mechanisms controlling myocardiogenesis and cardiomyocyte replacement during regenerative processes are not very well understood. In this brief review we try to give the answers to questions on certain aspects of myocardial tissue regeneration and engineering procedures.

Standard open repair versus minilaparotomy approach for abdominal aortic aneurysms: what is the best approach in patients with ischemic heart disease?

AIM

The beneficial effects of minilaparotomy approach in patients undergoing abdominal aortic aneurysm (AAA) repair have been defined. In this respect, the authors compared treatment outcome and procedure-related mortality rates of minilaparotomy technique with those of open standard repair in patients with ischemic heart disease.

METHODS

The authors retrospectively reviewed data on 212 patients who underwent elective AAA repair via a minilaparotomy approach at the Hospital of Istanbul over an 8-year period from February 1995 to January 2003. The clinical study included 46 patients who have only ischemic heart disease as a sole risk factor. This group was matched in a case-control fashion to a group of 57 patients with similar characteristics who were operated via standard median laparotomy. All available clinical, pathologic and postoperative data were reviewed and analyzed for postoperative outcome.

RESULTS

Mean operative times in mini- and standard laparotomy groups were 190+/-26 min and 165+/-15 min, respectively (P=0.32). Aortic clamping times did not differ significantly between two groups (61+/-12 min vs 53+/-10 min, P=0.43). Blood requirement was lower in minilaparotomy group. Five patients (8.7%) in the standard median laparatomy group died, while one death (2%) occurred in the other group (P<0.01). In patients who have undergone traditional repair, 5 patients suffered from myocardial infarction and 4 patients required prolonged mechanical ventilation. No coronary ischemic event was noticed in minilaparotomy patients. The minilaparotomy group had significantly shorter lengths of hospital (6.2+/-1.1 vs 9.3+/-2.8 days, P=0.03) and intensive care unit (ICU) stays (7.8+/-2.3 vs 14.5+/-3.2 hours, P=0.01). Duration of adynamic ileus (1.9+/-0.6 vs 2.8+/-1.1 days, P=0.02), return to normal diet (3.2+/-1.0 vs 4.6+/-1.3 days, P=0.01) and day of ambulation (1.5+/-0.3 vs 3.2+/-0.7 days, P=0.001) were significantly lower in the minilaparotomy group. The standard median laparotomy group was twice as costly as the minilaparotomy group (3 200+/-600 vs 5 900+/-900 US dollars, P=0.001).

CONCLUSION

The minilaparotomy technique has advantages that include less postoperative morbidity and mortality rates, early resumption of intestinal functions, reduced cost, decreased length of stay in the ICU and hospital. There-fore, the authors believe that this approach is still a valid alternative approach in the treatment of patients with AAA having ischemic heart disease as a risk factor.

Viability of the myocardium after twenty-four-hour heart conservation--a preliminary study

BACKGROUND

Orthotopic heart transplantation following ischemic times beyond four hours is associated with increased risk of early graft failure. The use of modern myocardial preservation strategies could enable safe transplantation after long-term conservation. In this study, we tested a new myocardial protection regime in an experimental model of 24 h storage.

METHODS

Orthotopic heart transplantations (n=15) were performed in a pig model. Donor hearts were flushed with Bretschneider solution, excised, and stored for 24 hours at 4 degrees C. During implantation, controlled reperfusions with substrate-enriched leukocyte-depleted blood cardioplegia were performed after each anastomosis. Blood cardioplegia contained 1 mmol/l of the Na(+)-H(+)-exchange inhibitor HOE 642 and 100 mg/l of adenosine. Controlled reperfusion was continued with leukocyte-depleted blood for 20 min. A microaxial pump was inserted after heart transplantation and circulatory assistance was maintained for five hours to prevent right heart failure.

RESULTS

No initial graft failure could be observed. Thirteen hearts could be weaned from extracorporeal circulation. Due to bleeding problems, kidney and lung failure only five hearts could be included in the final analysis. Hemodynamics of these hearts remained stable with epinephrine at 0.1 micro g/kg/min. Myocardial oxygen consumption 20 min after start of reperfusion (5.3+/-2.0 ml/100 g/min) did not differ significantly versus baseline (6.8+/-2.0 ml/100 g/min). Oxygen extraction six hours after heart transplantation was also well preserved compared to baseline (58.0+/-10.2 versus 49.2+/-8.8 %). Histological examination six hours after transplantation using luxol fast blue staining revealed that only 1.0 % of the myocytes were irreversibly damaged.

CONCLUSIONS

The data indicate full viability of the myocardium after 24 h conservation. The preservation technique described could contribute to the extension of conservation times in heart transplantation and enable transplantation of marginal donor hearts.