Open versus tunneling radial artery harvest for coronary artery grafting.

We present a less traumatic surgical technique for harvesting the radial artery as a coronary artery bypass graft that does not require any special equipment or skills. We prospectively randomized 40 patients undergoing coronary artery bypass grafting with the radial artery into two groups on the basis of harvest techniques: tunneling excision and conventional open method. The less-invasive tunneling technique is safe, easily applicable, and preferred by patients because of the superior cosmetic result.

Myocardial systolic strain is decreased after aortic valve replacement in patients with aortic insufficiency.

Background: Left ventricular three-dimensional nonlinear systolic strain determinations have potential to detect small decrements in ventricular function in patients with aortic insufficiency before and after aortic valve replacement.

Methods: Magnetic resonance imaging with tissue-tagging was performed on 42 normal volunteers and 14 patients with chronic aortic insufficiency both before and 28 +/- 11 months after aortic valve replacement. Preoperative and postoperative left ventricular volume, dimensions and ejection fraction were determined for all subjects.

Ventricular function after coronary artery bypass grafting: evaluation by magnetic resonance imaging and myocardial strain analysis.

Objective: Magnetic resonance imaging with radiofrequency tissue tagging permits quantitative assessment of regional systolic myocardial strain. We sought to investigate the utility of this imaging modality to quantitatively determine preoperative impairment and postoperative improvement in ventricular function in patients with ischemic heart disease.

Methods: Magnetic resonance imaging with radiofrequency tissue tagging was performed on 6 patients (average age 60.

Noninvasive, quantitative assessment of left ventricular function in ischemic cardiomyopathy.

Background: Coronary artery disease characteristically impacts left ventricular (LV) function on a regional basis, although ultimately global function may be affected as well. Echocardiography is commonly clinically used for the assessment of regional function; however, it is only semiquantitative and in its current iteration is only two-dimensional in nature. Magnetic resonance imaging (MRI) with tissue tagging offers the possibility for noninvasive, three-dimensional (3D) assessment of transmural and segmental left ventricular strain and, thereby, function.

Severe aortic insufficiency and normal systolic function: determining regional left ventricular wall stress by finite-element analysis.

Background: Because severe aortic insufficiency in the setting of preserved left ventricular function is often associated with a long asymptomatic period and unpredictable course on medical therapy, sensitive indices of left ventricular systolic performance are necessary for the optimal direction of therapeutic intervention. Because myocardial wall stress is closely related to both pathologic cardiac remodeling and ultimately to left ventricular decompensation, an accurate description of regional wall stress distribution may improve our ability to clinically manage these patients appropriately. The objectives of this study were (1) to define sensitive, noninvasive indices of left ventricular systolic performance to assist the clinician in the serial evaluation and early detection of increased left ventricular wall stress and, therefore, inadequate left ventricular remodeling and subsequent myocardial decompensation of patients with aortic insufficiency, and (2) to quantify differences in instantaneous global and regional end-systolic wall stress between normal subjects and patients.

Altered left ventricular geometry changes the border zone temporal distribution of stress in an experimental model of left ventricular aneurysm: a finite element model study.

Background: Left ventricular aneurysm (LVA) is a significant complication of myocardial infarction that may lead to global left ventricular (LV) dysfunction. However, the exact mechanism underlying the abnormal function has not been elucidated. In this study we tested the hypothesis that changes in LV geometry cause both an increase in wall stress and a change in the temporal distribution of stress in the LVA border zone (BZ) during systole.

Dynamic coronary MR angiography and first-pass perfusion with intracoronary administration of contrast agent.

Purpose: To evaluate whether dynamic imaging of the coronary arteries can be performed with intracoronary infusion of low-dose gadolinium (Gd)-based contrast agent and assess the effect of long duration and multiple infusions on the image signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR).

Materials And Methods: Dynamic coronary magnetic resonance (MR) imaging (130 msec/image) and contrast agent first pass myocardial perfusion studies were performed with intracoronary infusions of low-dose Gd-based MR contrast agent on dogs (N = 4) using a fast multislice gradient recalled echo (GRE) sequence.

Results: Contrast-enhanced coronary arteries were clearly imaged during infusion periods as long as 2.

Epicardial ablation on the beating heart: progress towards an off-pump maze procedure.

Background: The treatment of atrial fibrillation with unipolar radiofrequency (RF) catheter ablation techniques has been fraught with difficulty. This study was designed to evaluate the potential advantages of bipolar RF energy and its ability to create transmural linear lesions on the beating heart.

Methods: A right thoracotomy was performed on eight adult sheep.

Effect of target stenosis and location on radial artery graft patency.

Objective: The purpose of this study was to evaluate the effect of target vessel characteristics on radial artery patency when used as a composite T graft.

Methods: Between October 1993 and March 2001, 1022 patients underwent coronary bypass with the internal thoracic artery-radial artery composite T graft. Of these, angiography has been performed on 109 patients at a mean 27.