Lowell Steen

Failure of early heparin cessation as treatment for heparin-induced thrombocytopenia.

PURPOSE The complications of heparin-induced thrombocytopenia include thrombosis and death. The purpose of the study was to determine whether early heparin cessation can prevent these outcomes. SUBJECTS AND METHODS We performed a retrospective analysis of consecutive patients with heparin-induced thrombocytopenia diagnosed by platelet aggregometry. Demographic, clinical, and laboratory findings were compared in patients by whether heparin treatment was stopped early (< or = 48 hours) or late (>48 hours) after the onset of thrombocytopenia, as well as between patients with and without thrombosis. Thrombocytopenia was defined as a 50% decline in baseline platelet counts or an absolute platelet count < 100,000/mm3. RESULTS Of the 113 patients, 38% developed thrombosis and 27% died. One-half of patients had thrombosis diagnosed >24 hours after heparin cessation. No difference in thrombosis or mortality was found in the 40 patients with early heparin cessation [mean (+/-SD) time of cessation 0.7 +/- 0.6 days] compared with the 73 patients with late heparin cessation (5 +/- 3 days). Thrombosis >24 hours after heparin cessation occurred in 61% of the patients in the early group and in 40% of the late group (P = 0.17). In a multivariate analysis, only a lower nadir of the platelet count (percent of baseline) was associated with thrombosis. Neither thrombosis nor the time to heparin cessation were associated with mortality. CONCLUSIONS Early heparin cessation was not effective in reducing morbid events in patients with heparin-induced thrombocytopenia. Treatment strategies other than heparin cessation alone should be considered in patients with this condition.

Long-term clinical outcomes of real-world experience using sirolimus-eluting stents in saphenous vein graft disease

Objective: To evaluate the long‐term clinical outcomes of patients undergoing percutaneous coronary intervention for saphenous vein graft (SVG) disease. Specifically, we compared clinical endpoints of patients who received sirolimus‐eluting stents (SES) versus bare‐metal stents (BMS) for SVG disease. Background: A recent small randomized‐controlled trial (RCT) reported increased mortality with the use of SES in SVG disease. Methods: We retrospectively identified patients who underwent SES placement for a SVG lesion(s) at our institutions over a 4‐year period. The procedural and medical records were reviewed to identify predetermined clinical outcomes. Results: 318 patients who underwent SES placement for a SVG lesion were identified. 7 patients were lost to follow‐up. 141/311 patients (45%) received SES, while 170/311 (55%) received BMS. At a mean follow‐up of 34 months, there was a reduction in target lesion revascularization (TLR) (7% vs. 14%, P = 0.07) without an increased risk of mortality (6% vs. 12%, P = 0.06) in patients who received SES compared to patients who received BMS. When compared to the recent RCTs SES patients at long‐term follow‐up, our SES patients had significantly less mortality; rates of myocardial infarction, TLR, target vessel revascularization, and major adverse cardiac events; and were more likely to be taking dual antiplatelet and statin medications. Conclusion: Our results support that SES used in SVG lesions result in a reduction in TLR without an increased risk of mortality, and therefore may be an equally safe and feasible technique for revascularization with excellent long‐term clinical outcomes. These patients may benefit from prolonged dual antiplatelet and statin medication regimens.

Outcomes of Bare Metal versus Drug-eluting Stents in Allograft Vasculopathy

BACKGROUND Because of improved outcomes with drug-eluting stents (DES), we examined angiographic and clinical outcomes of bare metal stents (BMS) vs DES for discrete lesions in chronic allograft vasculopathy. METHODS Heart transplant patients who underwent percutaneous coronary intervention were divided into one of two groups: BMS or DES. Baseline clinical characteristics, rejection episodes and procedural details were compared. Distal arteriopathy was qualitatively compared using the Gao score. End-points included angiographic in-stent restenosis, acute coronary syndrome (ACS), ST-elevation myocardial infarction, heart failure admissions and cardiac death at 1 year. Students t-test, chi-square test and the Mann-Whitney U-test were utilized to assess the results. Correlations were assessed using Pearsons correlation coefficient. RESULTS Forty-two patients with 80 stents (56 DES, 24 BMS) were identified. Baseline clinical characteristics, immunosuppression regimen, cardiac risk factors, frequency of rejection and procedural details were similar. Distal arteriopathy was similar (p = 0.374), suggesting equally advanced vasculopathy. Twenty-nine patients (69%) and 46 lesions (58%) were available at 1 year for clinical and angiographic follow-up. One-year diameter stenosis (26.1 +/- 21.3% vs 31.7 +/- 38.3%; p = 0.602) and binary restenosis (22.6% vs 22.7%; p = 0.774) rates were similar for DES and BMS, respectively. There were no ST-elevation infarctions; ACS [9 (16%) vs 5 (21%) p = 0.638] and cardiac death (2 in both groups) were similar for DES and BMS, respectively. Heart failure admissions were more frequent in the DES group [18 (32%) vs 5 (21%); p = 0.016]. No clinical predictors were identified. CONCLUSIONS In-stent stenosis, ACS and cardiac death at 1 year were similar for DES and BMS. The milieu of systemic immunosuppression in heart transplant decreases the advantages of DES in allograft vasculopathy.

New catheter design for cannulation of the anomalous right coronary artery arising from the left sinus of valsalva

Cannulation of an anomalous right coronary artery during coronary angiography and percutaneous intervention poses significant technical difficulties using currently available catheter shapes. We describe a new catheter design and the cannulation technique for application of this catheter. The initial experience with this catheter in cases is reported. Catheter Cardiovasc Interv 2003;60:382–388.

Treatment of unprotected left main coronary artery stenosis with a drug eluting stent in a heart transplant patient with allograft vasculopathy.

High risk angioplasty with drug eluting stent placement into an unprotected left main coronary artery in a heart transplant recipient with allograft vasculopathy is reported. Ten month angiographic follow up is reported. The literature is reviewed and current methods of revascularisation are described in detail. This is the first report of drug eluting stent use in this clinical situation.

Usefulness of Wide Pulse Pressure as a Predictor of Poor Outcome After Renal Artery Angioplasty and Stenting

Renal artery stenosis is a common cause of secondary hypertension and ischemic nephropathy. Percutaneous angioplasty and stent placement has allowed select patients with renal artery stenosis to use fewer antihypertensive agents and improve or stabilize renal function. The associations of baseline systolic, diastolic, and pulse pressures (PPs) with outcomes of blood pressure (BP) and renal function were examined in 243 patients who underwent renal angioplasty and stent placement. The average PP before the procedure in patients with improvements or stabilizations in renal function was 53 +/- 20 mm Hg, compared to 107 +/- 18 mm Hg (p <0.05) in those with poorer outcomes. The average PPs before procedure were 47 +/- 15 mm Hg in those with improvements in BP, 82 +/- 10 mm Hg in those with stabilizations of BP, and 111 +/- 14 mm Hg in those with worsening BP. All findings were statistically significant (p <0.05). In conclusion, wide PP may reflect more advanced vascular stiffness and renal disease distinguishing patients less likely to benefit from revascularization.

Invasive assessment of mitral regurgitation: Comparison of hemodynamic parameters

Objectives: We sought to analyze several new hemodynamic characteristics which address the interplay of left atrial (LA) and left ventricular (LV) pressures, as well as to re‐analyze several other V wave characteristics employed in the determination of mitral regurgitation (MR) severity in order to determine which, if any, had adequate correlation with grade of MR for clinical utility. Background: Invasive assessment of mitral regurgitation includes analysis of intracardiac pressures and LV angiography. The V wave, when obtained from the pulmonary capillary wedge position (PCWP), and its various characteristics are believed to be of limited value for prediction of MR severity. Method: We analyzed the transeptal pressure tracings of patients with various degrees of MR. Several relationships from the simuItaneous pressure‐time curves of the LA and LV were defined. Biplane left ventricular angiography was used to grade MR. Correlation between each parameter and MR grade was determined by calculating a Pearson correlation coefficient. Results: The ratio of the area under the V wave to the LV systolic area (Va/LVa) best correlates with the degree of MR with a Pearson correlation coefficient of 0.60. The Va/LVa was significantly lower in patients with 0−1+ MR compared to ≥2+ MR (0.14 vs. 0.23 p = 0.002). Conclusions: Invasive hemodynamic assessment of MR severity could be enhanced by calculating our new ratio, Va/LVa, due to its ability to account for LV work that is lost to the LA with a proportional decrease in forward or useful LV work with progressively increasing severity of MR.

Thiazolidinediones Do Not Reduce Target Vessel Revascularization in Diabetic Patients Undergoing Percutaneous Coronary Intervention

Background: Animal studies have suggested that thiazolidinediones (TZDs) have antirestenotic properties. However, human data are lacking. The goal of this single-center study was to assess the target vessel revascularization (TVR) rate following percutaneous coronary intervention (PCI) among diabetic patients according to TZD use. Methods: A total of 325 consecutive diabetic patients who underwent PCI between January 2000 and December 2001 were included in the analysis. Among them, 82 patients were on TZD and 243 patients were on other hypoglycemic regimens. All patients were treated with stents and platelet glycoprotein IIb/IIIa inhibitors at the time of intervention. TVR and death/myocardial infarction/TVR were assessed at 1 year. Results: TZD patients were more likely to be younger, male and have hyperlipidemia. TVR occurred in 36.6% of TZD patients compared with 23.9% of non-TZD patients (p = 0.04). One-year death, myocardial infarction and TVR occurred in 41.1% of TZD patients compared with 30.8% of non-TZD patients (p = 0.04). Conclusion: In this retrospective analysis, TZD therapy did not decrease the need for repeat revascularization following PCI. Prospective randomized studies are warranted.

Comparison of primary percutaneous coronary intervention in patients with ST‐elevation myocardial infarction during and prior to availability of an in‐house STEMI system: Early experience and intermediate outcomes of the HARRT program for achieving routine D2B times <60 minutes

Over the last decade, significant advances in ST‐elevation myocardial infarction (STEMI) workflow have resulted in most hospitals reporting door‐to‐balloon (D2B) times within the 90 min standard. Few programs have been enacted to systematically attempt to achieve routine D2B within 60 min. We sought to determine whether 24‐hr in‐house catheterization laboratory coverage via an In‐House Interventional Team Program (IHIT) could achieve D2B times below 60 min for STEMI and to compare the results to the standard primary percutaneous coronary intervention (PCI) approach.

Presence of asymmetric dimethylarginine gradients across high-grade lesions in patients with coronary artery disease.

BackgroundAsymmetric dimethylarginine, an endogenous inhibitor of nitric oxide synthase, is a systemic marker of endothelial dysfunction. Although experimental evidence indicates that asymmetric dimethylarginine may play an important role in atherogenesis, local asymmetric dimethylarginine levels have not been measured in vivo. ObjectivesWe sought to determine whether: (i) asymmetric dimethylarginine is elevated locally at sites of coronary lesions, (ii) systemic asymmetric dimethylarginine concentrations correlate with local levels, and (iii) percutaneous coronary intervention produces immediate local asymmetric dimethylarginine elevation. MethodsIn patients undergoing percutaneous coronary intervention (n=15), blood samples were obtained from a peripheral venous site, the coronary ostium proximal to the lesion and the coronary vessel distal to the lesion, before percutaneous coronary intervention. Samples were also obtained distal to the coronary lesion immediately after percutaneous coronary intervention and from the peripheral venous line 24 h after percutaneous coronary intervention. ResultsAsymmetric dimethylarginine gradients were present across the coronary bed: local asymmetric dimethylarginine (μmol/l) was significantly higher distal to coronary lesions compared with proximally (2.39±1.27 vs. 1.52±0.68, P=0.005), and to systemic venous levels (2.39±1.27 vs. 1.17±0.72, P=0.001). Local asymmetric dimethylarginine did not increase immediately after percutaneous coronary intervention (1.88±0.89 vs. 2.39±1.27, P=0.11). Peripheral venous percutaneous coronary intervention levels 24 h after percutaneous coronary intervention were similar to baseline values (1.17±1.2 vs. 1.17±0.72, P=0.98). ConclusionAsymmetric dimethylarginine gradients exist across coronary lesions, suggesting asymmetric dimethylarginine release at the plaque site. Local asymmetric dimethylarginine accumulation may contribute to the endothelial dysfunction associated with high-grade coronary lesions. Peripheral asymmetric dimethylarginine is a marker of generalized endothelial dysfunction, but our findings highlight its limitation in detecting focal injury.