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Biomedical subjects

R R Heuser

Publications and source records attributed to R R Heuser.

At least 19 recordsLinked to original sources
PubMed1999

Low- versus high-dose recombinant urokinase for the treatment of chronic saphenous vein graft occlusion.

Recanalization of a totally occluded saphenous vein graft (SVG) using commercially available urokinase from human kidney cells has been shown to be effective, but the duration of infusion and complications such as allergic reactions, bleeding events, and non-Q-wave myocardial infarction have limited its acceptance. Recently, genetic engineering has allowed the synthesis of recombinant urokinase (r-UK). Patients with an occluded SVG from 37 centers were randomized to receive a 6-hour infusion of either low-dose (125,000 IU/hour) or high-dose (350,000 IU/hour) r-UK followed by up to a maximum of 18 hours of r-UK (125,000 IU/hour) via a subselective catheter directly into the occluded vein graft. The primary study end point was final preintervention achievement of Thrombolysis In Myocardial Infarction (TIMI) flow > or = 2 using core angiographic analysis. One hundred seven patients were randomized and 98 received the study drug (low dose 52 patients, high dose 46 patients). TIMI flow > or = 2 after completion of the study drug was higher in the high-dose group (51% vs 24%, p = 0.019). This difference narrowed, but a trend was still evident on the final angiogram after adjunctive mechanical intervention (72% vs 58%, p = 0.254). Bleeding complications were frequent; severe or life-threatening bleeding occurred in 12% of patients on the low dose and 11% of patients on the high dose (p = NS), including 2 intracerebral bleeds, both of which were fatal with 1 in each group. Thus, in patients with an occluded SVG, a randomized trial of direct low-dose versus high-dose r-UK infusion demonstrated increased recanalization rates (TIMI flow > or = 2) in the high-dose arm. Percutaneous revascularization of SVG with r-UK can be accomplished with acceptable success rates, but complications are frequent.

Adult↗
PubMed1998

Fracture of coronary guidewire during rotational atherectomy with coronary perforation and tamponade.

We present the case of a calcified right coronary artery lesion with a 90-degree exit angle. Attempts at rotational atherectomy led to wire transection and vessel wall perforation necessitating emergent pericardiocentesis and bypass surgery. We review the literature on complications of rotational atherectomy and the management of coronary perforations and retained guidewire fragments.

Atherectomy, Coronary↗
PubMed1998

Outpatient coronary angiography: indications, safety, and complication rates.

In the years since the introduction of outpatient cardiac catheterization and coronary angiography, the indications for the use of these procedures have expanded rapidly with advancements in surgical and endovascular procedures. The safety of outpatient coronary angiography has been well established, comparing very favorably with that of inpatient procedures. At present, a variety of different outpatient facilities exist. Catheterization laboratories may adjoin a hospital or be free-standing; the safety and success of procedures performed in mobile cardiac catheterization laboratories has also been described. There are a variety of access techniques for cardiac catheterization in use today, and there are many types and sizes of catheters available. Miniaturization of equipment has reduced complications and allowed early ambulation and discharge from outpatient laboratories. In addition, the development and refinement of catheters and techniques for achieving hemostasis may allow further reductions in patient stay and complications. The complication rates of outpatient cardiac catheterization and coronary angiography are, in fact, quite low--in some cases, lower complication rates are seen in the outpatient population than in the inpatient population. Although this is certainly related in part to the fact that outpatients generally have more stable disease, it is clear that careful equipment choices, proper technique, and adequate monitoring have contributed to the success of these important outpatient procedures.

Ambulatory Care↗
PubMed1997

Embolization of IMA side branch for post-CABG ischemia.

The existence of a chest wall "steal" of blood away from the myocardium through patent internal mammary artery branches has been hypothesized as a cause of recurrent angina pectoris after coronary artery bypass grafting. Although some authors believe that such a steal is physiologically impossible because coronary flow occurs in diastole and chest wall flow in systole, we recently documented ischemia in the left anterior descending coronary artery distribution before embolization of a large left internal mammary artery first intercostal branch that had been left intact at the time of operation. After embolization of the branch, clinical and objective evidence of ischemia resolved.

Coronary Artery Bypass↗
PubMed1996

Coronary thrombi increase PTCA risk. Angioscopy as a clinical tool.

BACKGROUND: The presence of angiographically identified intracoronary thrombus has been variably associated with complications after coronary angioplasty. Angiography has been shown to be less sensitive than angioscopy for detecting subtle details of intracoronary morphology, such as intracoronary thrombi. The clinical importance of thrombi detectable by angioscopy but not by angiography is not known. METHODS AND RESULTS: Percutaneous coronary angioscopy was performed in 122 patients undergoing conventional coronary balloon angioplasty (PTCA) at six medical centers. Unstable angina was present in 95 patients (78%) and stable angina in 27 (22%). Therapy was not guided by angioscopic findings, and no patient received thrombolytic therapy as an adjunct to angioplasty. Coronary thrombi were identified in 74 target lesions (61%) by angioscopy versus only 24 (20%) by angiography. A major in-hospital complication (death, myocardial infarction, or emergency bypass surgery) occurred in 10 of 74 patients (14%) with angioscopic intracoronary thrombus, compared with only 1 of 48 patients (2%) without thrombi (P = .03). In-hospital recurrent ischemia (recurrent angina, repeat PTCA, or abrupt occlusion) occurred in 19 of 74 patients (26%) with angioscopic intracoronary thrombi versus only 5 of 48 (10%) without thrombi (P = .03). Relative risk analysis demonstrated that angioscopic thrombus was strongly associated with adverse outcomes (either a major complication or a recurrent ischemic event) after PTCA (relative risk, 3.11; 95% CI, 1.28 to 7.60; P = .01) and that angiographic thrombi were not associated with these complications (relative risk, 0.85; 95% CI, 0.36 to 2.00; P = .91). CONCLUSIONS: The presence of intracoronary thrombus associated with coronary stenoses is significantly underestimated by angiography. Angioscopic intracoronary thrombi, the majority of which were not detected by angiography, are associated with an increased incidence of adverse outcomes after coronary angioplasty.

Adult↗