Concomitant David's operation and total arch replacement for acute type A aortic dissection.

A 61-year-old man complained of chest pain and developed congestive heart failure due to massive acute aortic regurgitation. Computed tomographic scan demonstrated Stanford type A aortic dissection from the aortic root to common iliac arteries. David's aortic valve sparing operation and total aortic arch replacement were applied to the patient, because the aortic dissection was extended into two aortic commissures and all arch vessels, though the tear was present at the proximal ascending aorta. The surgery was well tolerated without any significant complication.

[Outcome of aortic arch surgery in patients aged 70 years or older: axillary artery cannulation and selective cerebral perfusion supports].

OBJECTIVES: Axillary artery cannulation, selective cerebral perfusion and replacement of the ascending and arch aorta with an elephant trunk were evaluated to reduce cerebral complications in aortic arch surgery in patients with aortic aneurysm or aortic dissection involving the aortic arch. METHODS AND RESULTS: A total of 45 patients(18 with acute A type aortic dissection and 27 with chronic aortic aneurysm involving the aortic arch) aged 70-92 (mean age 74) years underwent total aortic arch replacement from March 1996 to May 2002. There were three operative deaths in patients with acute A type aortic dissection caused by massive cerebral infarction, bleeding and myocardial infarction, and one hospital death of sepsis. Overall in-hospital mortality was 8.9%(16.7% in A type dissection and 3.7% in chronic aneurysm). Operative complications included mediastinitis in four patients(9%), left recurrent laryngeal nerve palsy in eight(18%), and cerebral infarction in four(9%). Three of the patients with cerebral infarction had associated dissection-related cerebral ischemia before surgery. One patient died, and two needed a walking stick. Twelve of 18 patients(67%) with acute A type aortic dissection and 26 of 27 (96%) with chronic aortic aneurysm were discharged on foot. CONCLUSIONS: Axillary artery cannulation, selective cerebral perfusion and replacement of the ascending and arch aorta with an elephant trunk provided satisfactory operative results in elderly patients aged 70 years or older, especially in patients with chronic aortic aneurysm involving the aortic arch.

Aortic root replacement with stentless xenograft for aortic dissection.

This paper reviewed aortic root replacement with a stentless xenograft for Stanford Type A aortic dissection. Total aortic arch replacement plus aortic root reconstruction with a stentless xenograft was conducted in 2 patients with acute aortic dissection. In another 2 patients, aortic root replacement with a bioprosthesis was performed for chronic redissection of the aortic root which might be associated with the previous use of gelatin-resorcin-formalin glue. Full root replacement using this device is safe, reliable, reproducible, and technically less demanding. This device also provides a radical option for acute aortic dissection even in patients requiring concomitant aortic arch and root replacement.

Morphological changes of the arterial systems in the kidney under prolonged continuous flow left heart bypass.

We investigated morphological changes of the arterial systems in the kidneys under prolonged continuous flow left heart bypass. Twelve goats were subjected to 2 weeks of pulsatile left heart bypass followed by 4 weeks of continuous flow left heart bypass (group CF). After autopsy, the kidneys underwent pathological evaluation. Six normal healthy goats were used as controls. The media of the afferent arterioles of group CF were frequently thickened by an increase in the number of the mature smooth muscle cells (SMCs). The juxtaglomerular areas (JGA) were expanded because of an increase in the number and size of SMCs and/or SMC-like cells. Furthermore, the percentage of anti-proliferating cell nuclear antigen antibody-positive cells in the JGA of group CF (9.9 +/- 1.9%) was significantly higher (p = 0.025) than that of the control group (4.6 +/- 3.4%), indicating active proliferation in group CF. We concluded that prolonged continuous flow left heart bypass causes proliferation of SMCs and/or SMC-like cells in the afferent arterioles and their perivascular tissue.

Prostaglandin synthesis inhibitor prevents hypotension without impairing gut perfusion during normothermic cardiopulmonary bypass.

Aortic pressure declines during cardiopulmonary bypass (CPB), particularly at normothermia. It has been reported that administering vasoconstrictors during normothermic CPB (NCPB) to restore perfusion pressure might induce hypoperfusion of splanchnic organs. We have reported that prostaglandin (PG), metabolized in the lung but increased during CPB, might have played a substantial role in hypotension, and that a PG synthesis inhibitor (PGSI) could improve hypotension during CPB. This study was designed to examine whether regional perfusion of splanchnic organs was reduced when PGSI restored systemic perfusion pressure during NCPB. NCPB was performed in eight adult goats for 60 minutes (body weight 57.0 +/- 5.9 kg). PGSI was administered in group P (n = 4), while norepinephrine was administered in group C (n = 4), to keep aortic pressure in the range of 50 to 80 mm Hg. The total systemic flow was maintained at approximately 70 ml/kg/min. Tissue blood flow was measured by means of the colored microsphere method before and 30 and 60 minutes after the start of CPB. In group P, gut blood flows after the start of CPB were higher than those before CPB, significantly in the stomach and jejunum at 30 minutes (p < 0.05), whereas gut blood flows in group C were decreased or not changed. In conclusion, PGSI prevents hypotension without impairing gut perfusion during NCPB.