Panny Kallis

Comparison of two strategies for myocardial management during coronary artery operations

Despite the current trend for using blood cardioplegia, ventricular fibrillation with intermittent ischemia is still used as a strategy to manage the myocardium with impressive results. These two methods of myocardial management were compared in 40 patients undergoing elective coronary artery operations using creatine kinase MB isoforms and troponin T assays. Each patient was randomized to have either cold blood cardioplegia (n = 20) or ventricular fibrillation with intermittent ischemia (n = 20) for myocardial management during the construction of distal anastomoses. Until recently, the comparison of different methods of myocardial management has been hindered by the lack of a specific and sensitive marker of myocardial damage. Analysis of creatine kinase MB isoforms (MB2, cardiac tissue form; MB1, plasma-modified form) and cardiac-specific troponin T (a structural protein) has been shown to improve the sensitivity for the detection of myocardial damage. There were no significant differences between the two groups in age, sex ratio, extent of disease, or left ventricular function. Blood samples for analysis were collected before cross-clamp application and at time intervals up to 48 hours after. Median peak creatine kinase MB2 activity was found to be significantly higher in the blood cardioplegia group compared with ventricular fibrillation (26.5 U/L versus 19.5 U/L, respectively, p = 0.04). Although median peak troponin T concentration was higher in the blood cardioplegia group, the difference failed to reach significance (2.2 ng/mL versus 1.6 ng/mL, p = 0.15).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and hemodynamic evaluation of the 19-mm Carpentier-Edwards supraannular aortic valve

The clinical and hemodynamic performance of the 19-mm Carpentier-Edwards supraannular aortic valve is largely unknown compared with that of the larger valves. Over 4 years we implanted the 19-mm Carpentier-Edwards supraannular aortic valve into 21 patients (20 female) with a mean age of 75 +/- 1.2 years (range, 59 to 86 years) and a mean body surface area of 1.6 +/- 0.03 m2 (range, 1.3 to 1.7 m2). There were four deaths, one operative and three late noncardiac deaths. Follow-up of the 17 survivors for a mean of 20 +/- 3.1 months (range, 2 to 42 months) demonstrated symptomatic improvement in all 17 (all are now in New York Heart Association functional class I or II). There were no valve-related complications and no patient required long-term anticoagulation. Doppler echocardiographic studies were used to assess the in vivo hemodynamic profile of the valve. Mean postoperative aortic valve gradient was 34.1 +/- 2.7 mm Hg (range, 19 to 52 mm Hg). Functional valve orifice area was 1.1 +/- 0.09 cm2 (range, 0.6 to 1.8 cm2). Mean cardiac output was 3.92 +/- 0.17 L/min (range, 3.2 to 5.1 L/min) with a mean cardiac index of 2.5 +/- 0.11 L.min-1 x m-2 (range, 2.1 to 3.2 L.min-1 x m-2). In conclusion, we have demonstrated that aortic valve replacement with the 19-mm Carpentier-Edwards supraannular aortic valve has a low operative mortality and offers major clinical benefits despite moderate transprosthetic gradients. This approach provides an alternative management strategy in elderly patients who would otherwise require low-profile mechanical valves or aortic root enlargement.

Aortic root replacement and extraanatomic bypass for interrupted aortic arch in an adult

We describe an unusual case of interrupted aortic arch, aneurysmal ascending aorta, and aortic regurgitation in a 24-year-old man. He presented with general malaise, weakness of his legs, and hypertension. A single-stage operation was performed in which the aortic root was replaced with concomitant extraanatomic bypass of the interrupted segment of the aortic arch. He made a full recovery and has returned to work.

Pacing thresholds of temporary epicardial electrodes: Variation with electrode type, time, and epicardial position

We compared the variation in pacing thresholds of two widely used temporary pacing electrodes at different epicardial sites in 67 patients after coronary artery operations performed with either cardioplegia or ventricular fibrillation. In 33 patients, a bare, braided pacing wire (DW) was placed on the right ventricle and a Medtronic localized epicardial electrode (MED), on each ventricle. In the other 34 patients, the DW wire was placed on the right atrium and a MED electrode, on each atrium. Pacing thresholds were measured at the time of placement; at 1 hour, 6 hours, and 12 hours postoperatively; and daily for 4 days. The pacing thresholds (mean +/- standard error of the mean) at implantation were as follows: DW wire = 0.93 +/- 0.08 V and MED electrode = 0.63 +/- 0.1 V in the ventricles and DW = 1.28 +/- 0.18 V and MED = 0.65 +/- 0.09 V in the atria. On the fourth postoperative day, the pacing thresholds were DW = 2.08 +/- 0.21 V and MED = 1.19 +/- 0.22 V in the ventricles and DW = 2.33 +/- 0.29 V and MED = 1.04 +/- 0.09 V in the atria. The pacing thresholds of both types of wire increased significantly over time, but this deterioration was more pronounced with the braided wire both on the ventricle and on the atrium. The pacing threshold patterns were not affected by chamber side or mode of myocardial preservation. The braided ventricular wire failed to capture after 24 hours in 9 of 30 patients, whereas the localized epicardial electrode captured in all instances (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Exocrine pancreatic function in mediastinal teratomata: An aid to preoperative diagnosis?

The diagnosis of teratoma may be made by demonstration of high amylase content in fluid aspirated from anterior mediastinal lesions. In 2 cases of mediastinal teratoma proteolytic enzyme activity was evident at the time of operation. A diagnosis of mediastinal teratoma was aided in 2 subsequent cases by demonstration of elevated amylase activity in the aspirated fluid before definitive operation.

Rupture of a sinus of Valsalva aneurysm through the tricuspid septal leaflet

We report a case of rupture of an aneurysm of the noncoronary sinus of Valsalva with the tract of the fistula emerging through the tricuspid septal leaflet. This rare pathology created a diagnostic dilemma, as the direction of the jet of blood was alternating between the right atrium and the right ventricle.