Opening and closing characteristics of the aortic valve after valve-sparing procedures using a new aortic root conduit

BACKGROUND: The durability of aortic valve-sparing procedures is negatively affected by increased leaflet stress in the absence of normally shaped sinuses of Valsalva. We compared valve motion after remodeling procedures using a standard conduit and a specifically designed aortic root conduit. METHODS: Echocardiographic studies of the aortic valve dynamics were performed in 14 patients after remodeling of the aortic root (7 standard conduits, group A; 7 new conduits, group B) and in 7 controls (group C). Opening and closing leaflet velocities and percent of slow closing leaflet displacement were measured. Root distensibility and the pressure strain of the elastic modulus were measured at all root levels. RESULTS: Root distensibility and the pressure strain of the elastic modulus were different in group A and B only at the sinuses (p < 0.001). Opening and closing leaflet velocities were not different among groups. Slow closing leaflet displacement was markedly more evident in group B patients (24.2%+/-1.9% versus 2.5%+/-1.9% in group A, p < 0.001) and similar to controls (22.1%+/-7.9%). CONCLUSIONS: The new conduit guarantees dynamic features of the aortic valve leaflets superior to those obtained with standard conduits and more similar to normal subjects.     

Studies on the mechanism of reflex vasodilatation. The cholinergic component in the baroreceptorial reflex in the dog

This study was designed to investigate whether the cholinergic system is involved in the genesis of the reflex vasodilatation which follows the systemic hypertension induced by fast intravenous injection of norepinephrine in the dog. Accordingly, in 7 dogs the gracilis muscle was isolated and perfused and the reflex evoked. The analysis of the integrated areas of vasodilatation after atropine pretreatment showed a significant decrease of the reflex response in the perfused circulation. In fact, the mean value of the integrated areas of vasodilatation which was 66 +/- 8 mm Hg/min in the control condition, was reduced to 45 +/- 4 mm Hg/min after administration of atropine in the gracilis artery; meanwhile the integrated areas of systemic hypertension did not show any change. Phentolamine intra-arterial administration completely abolished the reflex. These results suggest the existence of a cholinergic component in the reflex vasodilatation induced by transitory baroreceptorial stimulation.     

Superficial wound dehiscence after median sternotomy: surgical treatment versus secondary wound healing

BACKGROUND: Superficial wound dehiscence after midline sternotomy is considered a minor complication in cardiac surgery, although it is quite frequent and requires prolonged medical treatment. It can be managed conventionally by topical treatment, with delayed secondary healing, or by surgical treatment and primary skin closure. We report the outcome of 96 patients who underwent conventional treatment, compared with a second group of 42 patients who underwent surgical treatment and direct closure. METHODS: From October 1999 to December 2002, 2400 consecutive patients underwent median sternotomy: 207 patients had sternal wound complications: 3 patients (0.125%) had mediastinitis, 66 patients (2.75%) had aseptic deep sternal wound dehiscence, and 138 patients (5.75%) had superficial wound dehiscence. The latter are the object of the present study; patients entered a protocol of skin wound care on an outpatient basis. The first 96 consecutive patients (group 1) required medications three times a week until complete healing. The last 42 patients (group 2) were treated by extensive surgical debridement of skin and subcutaneous tissue, direct closure of the superficial layers, and suture removal after 15 days. RESULTS: The two groups were comparable as to age, sex, and preoperative risk factors. The incidence of contaminated wounds was similar in the two groups (32 of 96 in group 1 and 11 of 42 in group 2; p = NS). The length of treatment was 29.7 days (range 2 to 144 days) for group 1 and 12.2 days (range 2 to 37 days) for group 2 (p < 0.0001). The mean number of medical treatments was 9.4 per patient in group 1 and 3.7 per patient in group 2 (p < 0.0001). CONCLUSIONS: Surgical debridement and primary closure of superficial surgical wound dehiscence after median sternotomy is a safe and valid treatment. Wound infection is not a contraindication to surgical treatment. Primary closure may contribute to reduce the risk for later infection. It also definitely contributes to decreasing healing time and strongly lessens patients' discomfort, diminishing hospital costs and hospital staff workload.     

Peripheral arterial disease: the magnitude of the problem and its socioeconomic impact

Peripheral arterial disease is a common disease in adults and its complications take a great toll in terms of quality of life and treatment costs. As healthcare budgets have taken up more of the economy, and as employers and patients have become concerned about the escalating costs of healthcare, we have entered an era in which individual doctors must become concerned about the costs of a service relative to its benefits. The purpose of this article is to review the literature on the pharmacoeconomics of the diagnostic and therapeutic procedures for peripheral arterial disease. It emerges that peripheral arterial disease places a great burden on healthcare systems and on society as a whole. Some of these costs, including indirect and intangible costs (i.e. those related to lost productivity, and reduced quality of life, respectively) could be reduced if the condition were to be recognized and correctly treated at an early stage.     

Postoperative aortic fistulas into the airways: etiology,pathogenesis, presentation,diagnosis, and management

Postoperative aortobronchial and aortopulmonary fistulas are rare and late complications of cardiac surgery. They mostly complicate descending thoracic aortic procedures. Hemoptysis is the main symptom, and may be massive or intermittent. The reported interval between the time of operation and the onset of hemoptysis ranges from 3 weeks to 25 years. Diagnostic examinations are often unable to directly visualize a fistula. Indication for surgical or endovascular repair mostly relies on clinical suspicion and nonspecific diagnostic features. Urgent treatment is based on the association of the following elements: (1) hemoptysis, (2) history of previous cardiac or aortic operation, (3) presence of lung infiltrates on the chest roentgenogram, (4) lung hemorrage on the computed tomographic scan, and (5) and visualization of a pseudoaneurysm. Aortobronchopulmonary fistulas are uniformly fatal if untreated. The overall surgical mortality rate is 15.3%. There is no procedure-related mortality after endovascular stent grafting. A review of the English-language literature from 1947 to October 2002 is presented.