Arthur J. Crumbley

The risk of small St. Jude aortic valve prostheses

We reviewed our 12-year experience with 254 adult patients who had St. Jude valves in the aortic position and used multivariate analysis to examine risk factors possibly affecting long-term morbidity and mortality. Nineteen-millimeter or 21-mm valves were implanted in 115 patients. Poor preoperative congestive heart failure status was associated with persistent congestive heart failure on late follow-up. Preoperative congestive heart failure and coronary artery disease were the only predictors of overall late death. Late deaths associated with heart failure and late sudden deaths were examined separately. Preoperative degree of heart failure was the only predictor of late death with associated heart failure. The implantation of a 19- or 21-mm valve in patients with a body surface area greater than 1.9 m2 somewhat increased the risk of late sudden death. In patients with a body surface area greater than 1.9 m2 and with a 19-mm or 21-mm annulus, consideration should be given to using a high-performance St. Jude valve or performing an annulus-enlarging procedure if this can be done with negligible morbidity.

St. Jude prosthesis for aortic and mitral valve replacement: a ten-year experience.

From January 1, 1979 through December 1990, 456 adult patients underwent isolated aortic (AVR) (254) or mitral (MVR) (202) valve replacement with the St. Jude prosthesis at the Medical University of South Carolina. Age ranged from 21 to 84 years (mean: 54 +/- 15 years for AVR; 51 +/- 13 years for MVR). Male sex predominated in the AVR group (66%) and female sex in the MVR group (64%). Ninety-two patients (20%) had associated coronary artery bypass grafting (AVR, 25%; MVR, 14%). There were 17 deaths (3.7%) occurring during the same hospitalization or within 30 days (AVR, 10/254 [3.9%]; MVR, 7/202 [3.5%]). Follow-up is 94.5% complete and ranges from 1.0 to 131 months (mean, 55 +/- 37 months; total, 2,073 patient-years). In the AVR group, 53 late deaths have occurred and actuarial survival is 80% +/- 3% at 5 years and 47% +/- 9% at 10 years. Twenty-one patients have sustained thromboembolic episodes (1.8%/patient-year), and the probability of remaining free of thromboembolism at 10 years is 67% +/- 13%. The mean improvement in New York Heart Association functional class from preoperative to postoperative is 3.1 +/- 0.76 to 1.6 +/- 0.84 (p < 0.0001). In the MVR group, there have been 41 late deaths, and the actuarial survival was 80% +/- 3% at 5 years and 63% +/- 5% at 10 years. Twenty-eight patients have sustained thromboembolic complications (2.9%/patient-year), and the probability of remaining free of thromboembolism at 10 years is 77% +/- 5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term experience with the St. Jude medical valve prosthesis

BACKGROUND All patients undergoing St. Jude Medical valve replacement at the Medical University of South Carolina since January 1979 have been followed prospectively at 12-month intervals. METHODS This report describes long-term experience in 710 adult patients undergoing isolated aortic (AVR) (418) or mitral valve replacements (MVR) (292) with this prosthesis from January 1979 to December 1996. RESULTS Ages ranged from 19 to 84 years (54.8 +/- 15.1 AVR, 51.8 +/- 12.9 MVR; mean +/- SD). Male gender predominated in the AVR group (70%) and female gender in the MVR group (62%). One hundred and fifty-seven patients (22%) had associated coronary artery bypass grafting (AVR 27%, MVR 15%). Thirty-day operative mortality was 5.3% (22/418) in the AVR group and 5.1% (15/292) in the MVR group. Follow-up is 96.9% complete and ranges from 1 month to 16.9 years (AVR, 2,376 patient-years, mean 5.7 +/- 4.5 years; MVR, 1,868 patient-years, mean 6.4 +/- 4.8 years). In the AVR group, 120 late deaths have occurred and actuarial survival was 78.0 +/- 2.3%, 58.0 +/- 3.2%, and 36.8 +/- 4.8%; at 5, 10, and 15 years, respectively. Forty-six patients have sustained 55 thromboembolic (TE) events (2.3%/patient-year). Fifty-one patients had anticoagulant-related bleeding complications (2.7%/patient-year). The mean improvement in New York Heart Association (NYHA) functional class from preoperative to postoperative was 3.0 +/- 0.8 to 1.7 +/- 0.1 (p < 0.05). In the MVR group, there have been 84 late deaths, and the actuarial survival was 79.3 +/- 2.5%, 60.1 +/- 3.5%, and 49.3 +/- 4.1% at 5, 10, and 15 years, respectively. Fifty-two patients have had 64 TE events (3.5%/patient-year). Twenty-three patients had anticoagulant-related bleeding complications (1.6%/patient-year). The mean improvement in NYHA functional class was from 3.3 +/- 0.6 to 1.8 +/- 0.1. There were no mechanical failures in either group. CONCLUSIONS With a follow-up now extending to 17 years, the St. Jude Medical valve continues to be a reliable mechanical prosthesis with low and stable rates of valve-related complications.

Twenty-Five Year Experience With the St. Jude Medical Mechanical Valve Prosthesis

BACKGROUND We evaluated all adult St. Jude mechanical valve recipients at our institution since the initial implant in January 1979 and now present our 25-year experience. METHODS Nine hundred forty-five valve recipients were followed prospectively at 12-month intervals from January 1979 to December 2007. RESULTS Operative mortality was 3% in the aortic valve recipients and 5% in the mitral valve recipients. Follow-up was 95% complete. Among aortic valve recipients, late actuarial survival was 81% +/- 2%, 59% +/- 2%, 41% +/- 3%, 28% +/- 3%, and 17% +/- 4% at 5, 10, 15, 20, and 25 years, respectively. Twenty-five-year freedom from reoperation, thromboembolism, bleeding, and endocarditis was 90% +/- 2%, 69% +/- 5%, 67% +/- 3%, and 9% 3 +/- 2% respectively. Among mitral valve recipients late actuarial survival was 84% +/- 2%, 63% +/- 3%, 44% +/- 3%, 31% +/- 3%, and 23% +/- 4% at 5, 10, 15, 20, and 25 years, respectively. Twenty-five-year freedom from reoperation, thromboembolism, bleeding and endocarditis was 81% +/- 10%, 52% +/- 8%, 64% +/- 6%, and 97% +/- 1%. Freedom from valve-related mortality and morbidity at 25 years was 26% +/- 7% and 29% +/- 6% for aortic and mitral valve replacement, respectively. Freedom from valve-related mortality was 66% +/- 8% and 87% +/- 3% for aortic and mitral valve replacement, respectively. CONCLUSIONS These results compare favorably with those for other mechanical prostheses. After two and a half decades of observation with close follow-up, the St. Jude mechanical valve continues to be a reliable prosthesis.

Differential effects of calcium channel antagonists in the amelioration of radial artery vasospasm

BACKGROUND Radial artery (RA) is being used for coronary artery bypass grafting (CABG) with greater frequency. However, RA is prone to post-CABG vasospasm, which may be neurohormonally mediated. Use of the calcium channel antagonist diltiazem has been advocated as a strategy to reduce post-CABG RA vasospasm. However, whether and to what degree different calcium channel antagonists influence neurohormonally induced RA vasoconstriction remains unknown. METHODS RA segments were collected from patients undergoing elective CABG (n = 13), and isometric tension was examined in the presence of endothelin (10 nM) or norepinephrine (1 microM). In matched RA, endothelin- or norepinephrine-induced contractions were measured in the presence of diltiazem (277 nM), amlodipine (73 nM), or nifedipine (145 nM). These concentrations of calcium channel antagonists were based upon clinical plasma profiles. RESULTS Endothelin and norepinephrine caused a significant increase in RA-developed tension (0.54+/-0.1 and 0.68+/-0.1 g/mg, respectively; p<0.05). Amlodipine or nifedipine significantly reduced RA vasoconstriction in the presence of endothelin (30+/-6% and 41+/-9%, respectively; p<0.05) or norepinephrine (27+/-8% and 53+/-9%, respectively; p<0.05), whereas diltiazem did not significantly reduce RA vasoconstriction. CONCLUSIONS These results demonstrate that neurohormonal factors released post-CABG can cause RA vasoconstriction, and that calcium channel antagonists are not equally effective in abrogating that response. Both amlodipine and nifedipine, which have a higher degree of vascular selectivity, appear to be the most effective in reducing RA vasoconstriction.

Cardiopulmonary bypass with bivalirudin in type II heparin-induced thrombocytopenia.

Cardiopulmonary bypass in patients with type II heparin induced-thrombocytopenia poses significant challenges. Inadequate pharmacokinetic profiles, monitoring, reversibility, and availability often limit alternative anticoagulation strategies. Bivalirudin, a semisynthetic direct thrombin inhibitor, was recently approved for use in patients undergoing percutaneous coronary interventions. Its unique properties, including a relatively short half-life, an anticoagulation effect that closely correlates with activated clotting time, and an alternate metabolic pathway for elimination, make bivalirudin an attractive agent for cardiopulmonary bypass in patients with type II heparin induced-thrombocytopenia. We report our experience using bivalirudin in 2 patients undergoing coronary artery bypass grafting.

Characterization of thromboxane A2/prostaglandin H2 receptors in human vascular smooth muscle cells

The present study utilizes a newly synthesized TXA2/PGH2 mimetic, I-BOP, to characterize the TXA2/PGH2 receptor in suspensions of cultured human vascular smooth muscle cells. [125I]-BOP bound in a saturable and specific manner (Kd = 2.6 +/- 0.6 nM; Bmax = 33,540 +/- 6,200 sites/cell; 69 fmoles/mg protein, n = 12). Competition binding assays were performed with [125I]-BOP and the TXA2/PGH2 receptor antagonists SQ29548, L657925 and L657926 and the receptor agonist U46619. I-BOP induced concentration-dependent increases in intracellular free calcium which were inhibited by SQ29548. The results provide radioligand binding evidence for the presence of a TXA2/PGH2 receptor in human vascular smooth muscle cells.

Use of Recombinant Activated Factor VII Concentrate to Control Postoperative Hemorrhage in Complex Cardiovascular Surgery

BACKGROUND Complex cardiovascular surgery often results in postoperative hemorrhage. Excessive blood product use may cause systemic thrombosis, end-organ dysfunction, and edema preventing chest closure. Recombinant activated factor VII (rFVIIa) concentrate may decrease hemorrhage where other treatment measures failed. We reviewed our experience with rFVIIa after complex cardiovascular surgery. METHODS A retrospective review evaluating 846 complex cardiovascular surgery patients of whom 36 received rFVIIa between January 1, 2001, and December 31, 2006, was performed. Efficacy and safety data were collected for the entire cohort in addition to delayed sternal closure requirements, reoperation, and operative mortality in the patient cohort temporally separated into two groups (pre-rFVIIa era, 2001 to 2003, 1 patient received rFVIIa; rFVIIa era, 2004 to 2006, 35 patients received rFVIIa). RESULTS A total of 36 patients received 41 rFVIIa doses with an in-hospital survival of 91.7%. Hemorrhage was controlled in 83.3% of patients, with 1 dose sufficient in 75.0%. There was a significant decrease (p < 0.005) in all blood product requirements post-rFVIIa compared with pre-rFVIIa administration. In the intensive care unit (n = 6), rFVIIa significantly reduced chest tube output (p = 0.028) and prevented reexploration for bleeding in 5 patients. The requirement for delayed sternal closure was significantly higher in the pre-rFVIIa era versus the rFVIIa era (p = 0.011). The incidence of thrombosis in all patients receiving rFVIIa was 11.1%. In the rFVIIa era, a higher incidence of postoperative renal failure (p = 0.005) and pneumonia (p < 0.002) was detected in patients receiving rFVIIa. CONCLUSIONS Recombinant activated factor VII appears to be effective in patients with refractory coagulopathy undergoing high-risk cardiovascular surgery.

Tricuspid valve repair for biopsy-induced regurgitation after cardiac transplantation.

Tricuspid regurgitation is a recognized complication of cardiac transplantation. Damage to the tricuspid valve and subvalvar apparatus has been suggested as a possible cause. We have repaired the tricuspid valves of 2 patients in whom severely symptomatic tricuspid regurgitation developed after transplantation. Gore-Tex sutures were used to replace ruptured chordae anchoring the septal and posterior leaflets. The repair was supported with a Carpentier-Edwards ring. The repairs remain durable at 2 year and 3 years. Both patients demonstrated a similar lesion that we believe to be characteristic of endomyocardial biopsy-induced tricuspid regurgitation.

Defects in Matrix Metalloproteinase Inhibitory Stoichiometry and Selective MMP Induction in Patients with Nonischemic or Ischemic Dilated Cardiomyopathy

The left ventricular (LV) myocardial collagen matrix has been proposed to participate in the maintenance of LV geometry. With several cardiac disease states such as dilated cardiomyopathy (DCM), alterations in extracellular matrix composition and structure have been reported to occur that may facilitate LV remodeling. 1–3 An important family of enzymes responsible for collagen remodeling are the matrix metalloproteinases (MMPs). 4,5 Several species of MMPs have been detected in the LV myocardium as well as the tissue inhibitors of MMPs, or TIMPs. 6 However, the molecular basis for changes in MMP/TIMP expression, MMP/TIMP stoichiometry, and the relation to MMP activity with nonischemic DCM and ischemic DCM remains unknown. Accordingly, the goal of the present study was to examine MMP/ TIMP species expression and MMP activity in patients with end-stage nonischemic and ischemic DCM.