BACKGROUND: Saddle-shaped annuloplasty rings are being increasingly used during mitral valve (MV) repair to conform the mitral annulus to a more nonplanar shape and possibly reduce leaflet stress. In this study utilizing three-dimensional transesophageal echocardiography we compared the effects of rigid flat rings with those of the saddle rings on the mitral annular geometry. Specifically we measured the changes in nonplanarity angle (NPA) before and after MV repair. METHODS: Geometric analysis on 38 patients undergoing MV repair for myxomatous and ischemic mitral regurgitation with full flat rings (n = 18) and saddle rings (n = 18) were performed. The acquired three-dimensional volumetric data were analyzed utilizing the "Image Arena" software (TomTec GmBH, Munich, Germany). Specifically, the degree of change in the NPA was calculated and compared before and after repair for both types of rings. RESULTS: Both types of annuloplasty rings resulted in significant changes in the geometric structure of the MV after repair. However, saddle rings lead to a decrease in the NPA (7% for ischemic and 8% for myxomatous MV repairs) (ie, made the annulus more nonplanar), whereas flat rings increased the NPA (7.9% for ischemic and 11.8% for myxomatous MV repairs) (ie, made the annulus less nonplanar); p value 0.001 or less. CONCLUSIONS: Implantation of saddle-shaped rings during MV repair surgery is associated with augmentation of the nonplanar shape of the mitral annulus (ie, decreases NPA). This favorable change in the mitral annular geometry could possibly confer a structural advantage to MV repairs with the saddle rings.

BACKGROUND: We used echocardiographically derived myocardial performance index (MPI) to assess changes in global right ventricular function with lung isolation. We hypothesized that changes in MPI with lung isolation may be related to the incidence of postoperative supraventricular tachycardia (SVT). METHODS: Transesophageal echocardiographic examinations were performed after induction of general anesthesia in patients undergoing elective lung resections. Doppler tissue imaging was used to calculate MPI at baseline and 10 minutes after institution of one-lung ventilation (OLV). Arrhythmias occurring within the first 5 postoperative days were recorded. RESULTS: Fifty-nine patients completed the study. Nineteen of 59 patients with a normal baseline MPI (0.40) had a higher incidence of SVT as compared with patients with an abnormal baseline MPI (42% versus 10%; p = 0.012). The MPI worsened during OLV in 46 patients; a worsening of MPI with lung isolation that was normal at baseline was associated with higher incidence of SVT (57% versus 0%; p = 0.045) compared with a worsening of MPI in patients with an abnormal baseline MPI (13% versus 6%; p = 0.62). A normal baseline MPI value that worsened after OLV, left atrial dilation, and advanced age were identified as predictors of postoperative SVT. CONCLUSIONS: Lung isolation is associated with acute changes in global right ventricular function. A normal baseline MPI that worsens after lung isolation is a better predictor of postoperative SVT as compared with baseline abnormal MPI that does not worsen after lung isolation. Myocardial performance index has a potential to be used as a right ventricular stress test to tolerate OLV before thoracic surgery.

We investigated the role of neuropeptide Y (NPY), abundant in the myocardial sympathetic nervous system and endothelial cells, in angiogenesis during chronic myocardial ischemia. Adult male Yorkshire swine underwent ameroid constrictor placement on the proximal left circumflex coronary artery. After 3 weeks, an osmotic pump was placed to deliver either placebo (control, n=8) or NPY(3-36) (NPY, n=8) to the collateral dependent region. Five weeks after pump placement, after cardiac catheterization and hemodynamic assessment, the heart was harvested for analysis. NPY treated animals demonstrated increased mean arterial pressures and improved left ventricular function (+dP/dt). Cardiac catheterization demonstrated a significant increase in the blush score in the NPY group (p0.001). Blood flow to the ischemic myocardium was not different between groups at rest or during ventricular pacing. Immunohistochemical double staining for CD-31 and smooth muscle actin demonstrated an increase in capillary and arteriole formation in NPY treated animals (p=0.02 and p0.001). Immunoblotting showed a significant upregulation of DPPIV (p=0.009) and NPY receptors 1 (p=0.008), 2 (p=0.02) and 5 (p=0.03) in the NPY treated group. Additionally, there was significant upregulation of VEGF (p=0.04), eNOS (p=0.014), phospho-eNOS (ser1177) (p=0.02), and PDGF (p0.001) in NPY treated group. The anti-angiogenic factors endostatin and angiostatin were significantly decreased in NPY treated animals (endostatin, p=0.03; angiostatin, p=0.04). Exogenous NPY(3-36) resulted in improved myocardial function and increased angiogenesis and arteriogenesis by stimulating growth factor, pro-angiogenic receptor upregulation, and decreasing anti-angiogenic expression, but did not increase blood flow to the ischemic myocardium. NPY may act as a good adjunct to primary agents of therapeutic angiogenesis.

BACKGROUND: Despite significant improvement in anesthetic and surgical techniques, the incidence of perioperative myocardial infarction (PMI) and all-cause mortality from any cardiac event during high-risk vascular surgery (abdominal aortic or infrainguinal revascularization procedures) remains high. In addition, there are significant health care costs associated with the management of PMI. OBJECTIVES: The aim of this analysis was to investigate the utility of routine preoperative myocardial stress testing prior to high-risk vascular surgery and the interventions performed based on the results of the testing. The outcome after surgery, based on sex of the patients, was also examined. METHODS: A retrospective analysis was performed on consecutive adult patients who had a positive dipyridamole-thallium stress test prior to high-risk vascular surgery in a university hospital (tertiary care center) between July 2001 and August 2004. The patients' preoperative demographic characteristics, perioperative record, and postoperative course in the hospital were analyzed. Combined major adverse outcome was defined as any incidence of MI, congestive heart failure, arrhythmias, renal failure, or death. RESULTS: Of a total of 503 patients, 160 had a positive stress test prior to high-risk vascular surgery (111 men, 49 women; mean [SD] age, 68 [11] and 70 [12] years, respectively). Men with a positive stress test who had either coronary intervention or perioperative β-blockade prior to surgery had a significant decrease in the incidence of combined major adverse outcomes (P = 0.02). Conversely, women did not have a significant improvement in outcome with either of the preoperative strategies. Using logistic regression, only age and conservative management in men were found to be predictors of adverse outcomes. CONCLUSIONS: In this small retrospective study, men with positive stress tests had fewer adverse events with either preoperative coronary revascularization or perioperative administration of β-adrenergic blocking drugs, compared with men who received no intervention. There were no significant differences in adverse outcomes between women with positive stress tests who received either treatment compared with those who did not receive any treatment.

Whereas the development of coronary stents has been a major breakthrough in the treatment of coronary artery disease, stent thrombosis, associated with myocardial infarction and death, has introduced a new challenge in the care of patients with coronary stents undergoing noncardiac surgery. This review presents the authors' recommendations regarding the optimal management of such patients. Elective surgery should be postponed for at least 6 weeks and optimally 3 months for a bare-metal stent and at least 1 year for a drug-eluting stent. On the other hand, managing a patient undergoing non-elective surgery is more difficult and necessitates a case-by-case assessment of bleeding risk versus thrombotic risk based on patient comorbidities, type of stents present, details of the coronary intervention, and type of surgical procedure. Patients with a risk of bleeding that outweighs the risk of stent thrombosis should discontinue at least clopidogrel, whereas all other patients should continue dual antiplatelet therapy throughout the perioperative period.