Biomedical subjects

Richard A Santa-Cruz

Publications and source records attributed to Richard A Santa-Cruz.

3 recordsLinked to original sources

PubMed2006

Aortic counterpulsation: a review of the hemodynamic effects and indications for use.

In the ever evolving field of cardiovascular medicine and coronary intervention, the intra-aortic balloon pump (IABP) is a mature technology, which still plays an important role. The balloon pump invasively supports patient hemodynamics by augmenting diastolic perfusion and increasing diastolic blood pressure, thereby increasing coronary perfusion and reducing afterload. Its efficacy has been demonstrated in a multitude of clinical situations, including acute coronary syndromes, high-risk coronary interventions, cardiogenic shock, and cardiovascular surgery. The potential complications of aortic counterpulsation are serious, although much lower than once feared. With proper patient selection, insertion technique, and management, the IABP is a powerful tool to assist in the treatment of patients with cardiovascular disease. This article will review the hemodynamics, indications, and complications associated with its use.

Angina, Unstable↗

PubMed2005

Clinical predictors and characteristics of patients with chronic liver disease and intrapulmonary shunts.

BACKGROUND: Intrapulmonary shunting (IPS) is a well-described phenomenon in chronic liver disease but its significance is not known. HYPOTHESIS: The study was undertaken to enhance our understanding of the characteristics and prevalence of IPS. METHODS: We retrospectively studied 204 consecutive patients with end-stage chronic liver disease who underwent a dobutamine stress echocardiogram, along with a saline contrast bubble study, as part of their pretransplant evaluation. RESULTS: Intrapulmonary shunting of any degree was present in 56.4% of patients. Patients with IPS were more likely to report alcohol use and less likely to have diabetes mellitus. Patients in Child-Pugh classification C were more likely to have IPS than those with classification A or B. The resting room air PaO2 levels were significantly lower in patients with grade 3-4 IPS than in those with grade 1-2. Elevated estimated pulmonary systolic pressure on echocardiography was more prevalent in patients with than in those without IPS. CONCLUSIONS: A majority of patients with end-stage chronic liver disease undergoing transplant evaluation have IPS. There are important baseline differences between patients with and without IPS. The presence of IPS is associated with increased severity of chronic liver disease. Further study is required to define the prognostic significance of IPS and its impact on future liver transplantation.

Adult↗

PubMed2004

Clopidogrel: how good is it and how does it work?

Until recently, long-term antiplatelet therapy for the treatment and prevention of the complications of atherothrombotic disease was limited to aspirin. Although an incredibly cost-effective therapy, in placebo-controlled clinical trials approximately 75% of patients at risk continue to experience thrombotic events despite chronic aspirin therapy. The availability of the thienopyridines, in particular clopidogrel, represents an important addition to the physician's armamentarium. A number of clinical trials have confirmed the efficacy of the combination of clopidogrel and aspirin therapy compared with aspirin alone, with multiple other important large-scale clinical trials currently ongoing. The exact mechanism of this benefit is still being elucidated but is clearly related to the inhibition of the many consequences of platelet activation--vascular inflammation, endothelial dysfunction, and localized angiogenesis/mitogenesis--and not just aggregation.

Aspirin↗