Jeffrey A. Hirst

Results of primary percutaneous transluminal coronary angioplasty plus abciximab with or without stenting for acute myocardial infarction complicated by cardiogenic shock

This study examines the effects of abciximab as adjunctive therapy in primary percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI) complicated by cardiogenic shock. Abciximab improves the outcome of primary PTCA for AMI, but its efficacy in cardiogenic shock remains unknown. Case report forms were completed in-hospital and follow-up was obtained by telephone, outpatient visit, and review of hospital readmission records. A total of 113 patients with cardiogenic shock from AMI were included. All underwent emergency PTCA during which abciximab was administered to 54 patients (48%). The 2 groups of patients who received and did not receive abciximab were similar at baseline. Coronary stents were implanted slightly more often in the abciximab group (59% vs 42%; p = 0.1). A significantly improved final TIMI flow, less no-reflow, and a decrease in vessel residual diameter stenosis occurred in the abciximab group. At 30-day follow-up, the composite event rate of death, myocardial reinfarction, and target vessel revascularization was better in the abciximab group (31% vs 63%; p = 0.002). The combination of abciximab and stents was synergistic and resulted in improvement of all components of the composite end point beyond that seen with each therapy alone. Thus, abciximab therapy improves the 30-day outcome of primary PTCA in cardiogenic shock, especially when combined with coronary stenting.

Intracardiac echocardiography in humans using a small-sized (6F), low frequency (12.5 MHz) ultrasound catheter methods, imaging planes and clinical experience

OBJECTIVES This study was designed to determine the clinical utility and feasibility of using 12.5-MHz ultrasound catheters for intracardiac echocardiography. BACKGROUND Intracardiac echocardiography is a potentially useful technique of cardiac imaging and monitoring in certain settings. The feasibility of intracardiac echocardiography using 20-MHz ultrasound catheters in patients has been demonstrated. High resolution images of normal cardiac structures as well as cardiac abnormalities have been obtained. However, imaging has been limited by the shallow depth of field inherent in high frequency ultrasound imaging. METHODS Intracardiac echocardiography with 12.5-MHz catheters was performed in eight mongrel dogs and 92 patients. Catheters were introduced percutaneously in 80 patients studied in the catheterization laboratory and directly into the heart in 12 patients in the operating room. Right heart imaging was performed in 68 patients and arterial and left heart imaging in 35 patients. RESULTS When these catheters were introduced into the venous system, the right atrium, tricuspid valve, right ventricle, pulmonary valve and pulmonary artery were visualized. Pericardial effusion, intracardiac masses and atrial septal defects were correctly identified. The left ventricle, left atrium, mitral valve, aortic valve, aorta and coronary arteries could be imaged from the arterial circulation. Diseases identified included valvular aortic stenosis, subvalvular aortic stenosis and Kawasaki disease. Average imaging time was 10 min. No complications occurred as a result of intracardiac echocardiography. CONCLUSIONS Intracardiac echocardiography with 12.5-MHz ultrasound catheters is safe and feasible; it also provides anatomic and physiologic information. This feasibility study provides a foundation for wider clinical use of intracardic echocardiography.

Duration of Abnormal SPECT Myocardial Perfusion Imaging Following Resolution of Acute Ischemia: An Angioplasty Model

OBJECTIVES This study was designed to determine how long nuclear myocardial perfusion imaging (MPI) remains abnormal following transient myocardial ischemia. BACKGROUND Acute rest MPI identifies myocardial ischemia with a high sensitivity when the radionuclide is injected during chest pain. However, the sensitivity of this technique is uncertain when the radionuclide is injected following the resolution of symptoms. METHODS Forty patients undergoing successful coronary angioplasty were randomized into four equal groups. Tc-99m sestamibi was injected intravenously during the last balloon inflation (acute MPI) in 30 patients and then reinjected 1, 2, or 3 h later (delayed MPI). In a fourth group, the radiopharmaceutical was injected at 15 min following balloon deflation (delayed MPI). A final injection was performed at 24 to 48 h (late MPI) in 37 patients (93%). RESULTS A perfusion defect was detected in all 30 acute MPI studies; in 7/10 patients (70%) injected at 15 min; in 11/30 patients (37%) injected at 1, 2, or 3 h; and in 7/37 patients (19%) injected at 24 to 48 h. Perfusion scores were 13.0 +/- 9.2 on acute MPI, 5.1 +/- 2.8 at 15 min (p < 0.001 vs. acute MPI); 2.6 +/- 3.0 at 1, 2, and 3 h (p < 0.001 vs. acute MPI); and 1.3 +/- 2.4 at 24 to 48 h (p < 0.001 vs. acute MPI; p < 0.03 vs. delayed MPI). CONCLUSIONS Myocardial perfusion imaging may remain abnormal for several hours following transient myocardial ischemia even when normal flow is restored in the epicardial coronary artery.

Short- and medium-term outcome differences in women and men after primary percutaneous transluminal mechanical revascularization for acute myocardial infarction.

Women presenting with acute myocardial infarction (AMI) have a higher mortality with conventional medical and thrombolytic therapy when compared with men. The outcome after primary percutaneous transluminal mechanical revascularization has not yet been fully investigated. This study was performed to compare the characteristics and the short- and medium-term outcomes of women and men with AMI treated with primary percutaneous revascularization. A total of 182 consecutive patients (62 women and 120 men) were included. Baseline clinical characteristics were similar except that women were older than men, presented more often in cardiogenic shock, and had smaller reference vessel diameters. Stents and abciximab were used equally, but abciximab was stopped more often in women before completion of the 12-hour infusion because of higher bleeding rates. Acute procedural success rates were similar (92% and 97%) but mortality was much higher in women, both at 30-day follow-up (100% vs 0.9%; p <0.05) and during a mean follow-up of 6.9 +/- 4.1 months (15% vs 4.4%; p <0.05). Women also experienced more unfavorable cardiovascular events (recurrent unstable angina or AMI, target vessel revascularization) than men. However, after control for baseline clinical differences in a multivariate analysis, gender was not an independent predictor of survival, whereas age, cardiogenic shock, and completion of a 12-hour abciximab infusion were.

Abciximab in primary coronary angioplasty for acute myocardial infarction improves short- and medium-term outcomes

OBJECTIVES The purpose of this study was to compare the outcome of primary percutaneous transluminal coronary angioplasty for acute myocardial infarction (MI) when performed with or without the platelet glycoprotein IIb/IIIa antibody, abciximab. BACKGROUND Abciximab improves the outcome of angioplasty but the effect of abciximab in primary angioplasty has not been investigated. METHODS Data were collected from a computerized database. Follow-up was by telephone or review of outpatient or hospital readmission records. RESULTS A total of 182 consecutive patients were included; 103 received abciximab and 79 did not. The procedural success rate was 95% in the two groups. At 30-day follow-up, the composite event rate of unstable angina, reinfarction, target vessel revascularization and death from all causes was 13.5% in the group of patients who did not receive abciximab, 4% (p < 0.05) in the abciximab group and 2.4% (p < 0.05) in the subgroup of patients (n = 87) who completed the 12-h abciximab infusion. At the end of follow-up (mean 7+/-4 months), the composite event rate was 32.4%, 17% (p < 0.05) and 13.1% (p < 0.01) in these three categories respectively. Abciximab bolus followed by a 12-h infusion was an independent predictor of event-free survival, in a Cox proportional hazards model (relative risk 0.49; 95% confidence interval 0.24 to 0.99; p < 0.05). CONCLUSIONS Abciximab given at the time of primary angioplasty may improve the short- and medium-term outcome of patients with acute MI, especially when a 12-h infusion is completed.

First Experience With Implantation of a Percutaneous Right Ventricular Impella Right Side Percutaneous Support Device as a Bridge to Recovery in Acute Right Ventricular Infarction Complicated by Cardiogenic Shock in the United States

We report the first implantation in the United States of a novel percutaneous right ventricular (RV) support device as a bridge to recovery in a patient with RV infarction with cardiogenic shock refractory to standard care. A 64-year-old man, with prior inferior wall myocardial infarction treated with percutaneous coronary intervention, presented with late drug-eluting stent thrombosis inferoposterior ST-segment–myocardial infarction complicated by cardiac arrest requiring defibrillation of ventricular tachycardia (Figure 1; Movie I and II in the online-only Data Supplement). Despite revascularization, fluid administration to a central venous pressure of 20 mm Hg, dobutamine and vasopressin infusions, and intra-aortic balloon pump counterpulsation, he remained in RV shock (cardiac index of 1.8 L/min per m2). With use of antiplatelet drugs, surgical cannulation for extracorporeal support was deemed an excessive risk. Figure 1. Acute inferoapical ST-elevation–myocardial infarction (STEMI) treated …

TRAUMATIC INTRAMYOCARDIAL DISSECTION SECONDARY TO SIGNIFICANT BLUNT CHEST TRAUMA: A CASE REPORT

The case of a patient with delayed mitral regurgitation and right coronary artery traumatic injury in association with intramyocardial dissection without rupture or pseudoaneurysm is presented. These findings evolved secondary to blunt chest trauma and were confirmed by cardiac ultrasound scanning, magnetic resonance imaging, and cardiac catheterization. Successful surgical correction was facilitated with this combination of diagnostic testing.

Bailout antegrade coronary reentry with the stingray™ balloon and guidewire in the setting of an acute myocardial infarction and cardiogenic shock

Emergent coronary artery bypass surgery for failed percutaneous coronary intervention (PCI) during acute myocardial infarction (MI) is a bailout strategy that is associated with a high in‐hospital morbidity and mortality (7–10%). Innovative strategies to improve the probability of PCI success in this setting are needed. Antegrade coronary re‐entry with the Stingray™ balloon and guidewire has been shown to facilitate recanalization of chronic total occlusions in stable patients. We report a case where the Stingray™ device was successfully used as a bailout strategy in the setting of an acute MI complicated by cardiogenic shock.

Maintenance of coronary guidewire position during guide catheter exchange

Maintaining the position of a guidewire across coronary artery lesions during angioplasty is important to permit rapid and reliable access. This article describes a technique which enables a guide catheter to be replaced while maintaining coronary guidewire position by using an additional, larger guidewire for support to prevent dislodgment of the coronary guidewire.

Site-specific intracoronary thrombolysis with urokinase-coated hydrogel balloons: Acute and follow-up studies in 95 patients

Conventional balloon angioplasty in the presence of intracoronary thrombus is associated with an elevated risk for acute myocardial infarction, emergency bypass surgery, and death. The purpose of this study was to assess the safety and efficacy of a new technique to treat thrombus-containing stenoses consisting of the local delivery of urokinase directly to the site of intraluminal clot with hydrogel-coated balloons. Ninety-five patients with angiographically apparent intracoronary thrombus were treated with urokinase-coated hydrogel balloons either prior to (n = 74) or following (n = 21) conventional balloon angioplasty. Clinical diagnoses for the study group included acute myocardial infarction in 50 patients, postinfarction angina in 23 patients, and unstable angina in 22 patients. All hydrogel balloons were initially coated with urokinase by immersing the inflated balloon in a concentrated Abbokinase solution (50,000 units/ml) for 60 s. All patients were subsequently treated with drug-coated balloons using a balloon:artery ratio of 1:1, a mean of 2.2 +/- 1.2 inflations, and a mean total inflation time of 7.5 +/- 4.9 min. Use of urokinase-coated balloons resulted in angiographic disappearance of intracoronary thrombus in 78 patients, improvement in 14, and no change in the remaining 3 patients. Following hydrogel balloon use for the entire 95 patients, TIMI flow increased from 1.4 +/- 1.2 to 2.9 +/- 0.4, minimal lumen diameter increased from 0.4 +/- 0.4 to 2.0 +/- 0.6 mm, and thrombus score decreased from 2.0 +/- 0.9 to 0.2 +/- 0.6 (all P < 0.01). Procedural and early in-hospital complications were noted in 7 of the 95 patients (7.4%) and included abrupt closure in 3 patients, distal embolization in 1 patient, no reflow in 1 patient, sidebranch occlusion in 1 patient, and late closure in 1 patient. Two of the 3 patients with abrupt closure and the single patient with late closure required intracoronary stenting to maintain vessel patency. Two of these 7 patients sustained small myocardial infarctions, although no patient required emergency bypass surgery or experienced a procedural death. Late clinical follow-up (mean = 8.3 +/- 6.6 months; range = 2 wk to 29 mo) demonstrated adverse recurrent events in 29 of the 95 patients (30.5%), including death (n = 5), myocardial infarction (n = 2), and recurrence of angina (n = 22). The results of this study suggest that intracoronary thrombolysis can be safely and rapidly achieved by using limited quantities of urokinase delivered directly to the site of intraluminal clot with hydrogel balloons. Use of this technique may result in improved acute outcomes in comparison with conventional techniques currently being used to treat thrombus-containing stenoses.