In normal hearts, the annulo-papillary muscle distances of the mitral apparatus are similar in 2-, 4-, 8-, and 10-o'clock positions and correlate with the mitral annular diameter.

From 1987 to February 1991, we have repaired or replaced the aortic arch in ten patients using deep hypothermic systemic circulatory arrest with continuous retrograde cerebral perfusion (CRCP). CRCP can be implemented using the bypass connecting the arterial and venous lines of the extracorporeal circuit to reverse the flow into the superior vena cava cannula after induction of circulatory arrest. CRCP flow required to maintain an internal jugular vein pressure of 20 mmHg ranged from 100 to 500 ml/min. After completion of suturing of the aortic arch graft, air is evacuated retrogradely from the open arch vessels prior to reestablishing the usual arterial return. Two patients died, one from sepsis and the other from liver cirrhosis 1 month postoperatively. CRCP times ranged from 11 to 56 min, and minimal nasopharyngeal temperatures ranged from 16 degrees to 18 degrees C. The difference in oxygen content between the perfused blood and the blood draining from the arch vessels during CRCP most likely reflected the steady-state metabolism of the brain during the deep hypothermic state. This technique offers advantages including the need for dissecting and clamping the arch branches, providing sufficient metabolic support to the brain during deep hypothermia, and eliminating embolism of particulate debris from the aortic arch.

No abstract

No abstract

No abstract

No abstract

Mitral valve replacement with maintenance of mitral annulopapillary muscle continuity in patients with mitral stenosis Postoperative left ventricular performance was evaluated in patients with mitral stenosis who underwent mitral valve replacement with maintenance of the continuity of the mitral anulus and papillary muscles. Mitral valve replacement with preservation of autologous chordae tendineae (n = 7) or their replacement with expanded polytetrafluoroethylene sutures (n = 14) was performed in 21 patients with mitral stenosis. Hemodynamic parameters were compared with those of 28 patients who underwent conventional mitral valve replacement and 27 patients who underwent open mitral valve commissurotomy. No deaths occurred in the early or late follow-up period. All hemodynamic parameters were improved after the operation, and no significant differences were detected among the three groups with regard to postoperative cardiac index or mitral valve area. No significant differences were observed in left ventricular end-diastolic volume index, end-systolic volume index, or contractility index, but the postoperative left ventricular ejection fraction in the chordal preservation and open commissurotomy groups was greater than that in the group having conventional mitral valve replacement. Postoperative regional shortening was greatest at the diaphragmatic portion in the chordal preservation group and at the long axis in the open commissurotomy group. In the mid-term postoperative period, although no differences were noted among the three groups in echocardiographic data or global ejection fraction measured by multigated equilibrium radionuclide angiography, the regional shortening at the anterolateral portion of the left ventricle in the chordal preservation and commissurotomy groups was greater than that in the group having conventional mitral valve replacement. Postoperative radionuclide angiography during exercise failed to demonstrate any difference between the ejection fraction in the chordal preservation group and that in the group having conventional mitral valve replacement. (J THORAC CARDIOVASC SURG 1994;108:42-51) Yutaka Okita, MD* (by invitation), Shigehito Miki, MD (by invitation), Yuichi Ueda, MD (by invitation), Takafumi Tahata, MD (by invitation), Tetsuro Sakai, MD (by invitation), and Katsuhiko Matsuyama, MD (by invitation), Nara, Japan Sponsored by Tadaomi Miyamoto, MD, Kitakyushu, Japan Eservation of the continuity between the mitral anulus and the papillary muscles results in improved postopera-From the

Deep hypothermic circulatory arrest has been widely used as an adjunct for surgery of the aortic arch to protect the brain and other vital organs. We introduced the use of continuous retrograde cerebral perfusion via the superior vena cava during deep hypothermic circulatory arrest in 1987 and have used it in 33 patients. Continuous retrograde cerebral perfusion times ranged from 10 to 89 minutes (mean 40.2 +/- 22.5), and minimal nasopharyngeal temperatures ranged from 14 to 25 degrees C (mean 17.4 +/- 2.0). Two patients with a ruptured aneurysm died during operation due to bleeding and two other patients, with continuous retrograde cerebral perfusion time of 24 and 35 minutes, died 1 month postoperatively due to preoperative liver cirrhosis and sepsis. Two patients suffered from stroke. The remaining 27 patients, including 6 with from 60 to 82 minutes of continuous retrograde cerebral perfusion, had no complications related to continuous retrograde perfusion. During continuous retrograde cerebral perfusion, 66 pairs of blood samples from the perfusate and from the drainage back to the arch vessels were obtained. Analysis of these samples revealed that partial pressure of oxygen, saturation of oxygen, and oxygen content significantly decreased (p < 0.001), and partial pressure of carbon dioxide (CO2) and CO2 content significantly increased (p < 0.001). The nasopharyngeal temperature gradually increased at the rate of 0.01 to 0.03 degree C/min, but was maintained below 20 degrees C. These results reflect the fact that the aerobic metabolism of the brain is maintained during continuous retrograde cerebral perfusion due to oxygen and substrate availability. This technique offers the potential of metabolic support to the brain during deep hypothermic circulatory arrest and prolongs the safe time limits of deep hypothermic circulatory arrest in surgery of the aortic arch.