Laser angioplasty of totally occluded coronary arteries and vein grafts: Preliminary report on a current trial

Laser angioplasty of totally occluded coronary arteries and vein grafts: Preliminary report on a current trial

ABSTRACTS group required admission. The authors concluded that frequent high doses of nebulized albuterol appear to be safe and effective for treatme...

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ABSTRACTS

group required admission. The authors concluded that frequent high doses of nebulized albuterol appear to be safe and effective for treatment of otherwise healthy children with severe acute asthma. They also concluded that the side effects of high-dose therapy are mild and temporary. Bruce Spears, MD ventricular tachycardia, wide complex

Wide QRS tachycardia adult

in t h e c o n s c i o u s

Steinman RT, Herrera C, Schuger CD, et al JAMA 261:1013-1016

Feb 17, 1989

The last ten years have seen a significant improvement in our understanding of wide complex tachycardia. This article addresses the relationship between hemodynamic stability and wide QRS tachycardia etiology. Twenty consecutive patients with wide complex tachycardia who were conscious, alert, and oriented were analyzed prospectively. Electrolyte imbalance, acute myocardial infarction, and drug reactions were excluded. Twelve-lead ECGs were obtained in 18 of the patients, r h y t h m strips in the remaining two. The following ECG criteria supported the diagnosis of ventricular tachycardia: atrioventricular dissociation, QRS duration greater than 0.14 s, left axis deviation, and Wellens' morphological criteria for the QRS complex. Following conversion to sinus rhythm, electrophysiologic testing was performed in 17 of the patients. Using both ECG criteria and electrophysiologic testing results, a diagnosis of ventricular tachycardia was made in 85% of the patients, supraventricular tachycardia in the remaining 15%. Interestingly, heart rate was noted and found to be more than 200 in two thirds of the patients with proven ventricular tachycardia. The authors strongly suggest that we avoid the pitfall of associating hemodynamic stability with less malignant rhythms. Furthermore, they point out that ventricular tachycardia is frequently much faster than the classic rate of 140. Robinson Nicholson, MD

laser, angioplasty, coronary artery disease

L a s e r a n g i o p l a s t y of t o t a l l y o c c l u d e d c o r o n a r y a r t e r i e s a n d vein grafts: P r e l i m i n a r y r e p o r t on a c u r r e n t t r i a l Foschi A, Myers G, Crick WF, et al Am J Cardiol 63:9F-13F

Apr 1989

This report is one of the first on the treatment of severe coronary artery disease with laser angioplasty. Percutane-

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ous transluminal coronary angioplasty (PTCA) has been used successfully in lieu of coronary artery bypass grafting (CABG) for symptomatic patients with severe stenosis of coronary arteries. However, totally occluded arteries or bypass grafts have remained as unsolved challenges for PTCA. Laser angioplasty appears to be a viable option for these patients. Three investigators have treated totally occluded coronary arteries and vein grafts in 34 patients with 36 coronary laser procedures with a recanalization rate of 92%. All lesions were refractory to medical therapy and PTCA. After recanalization is achieved, conventional PTCA is used to dilate the artery. The laser system is intended to be an adjunctive debulking procedure. There were no complications attributable to the laser. There were no thermal or mechanical vessel perforations, and no emboli or acute reclosures. However, the problem of restenosis remains, with three patients having reclosure of the recanalized arteries during the clinical trial. Occluded vein grafts account for one third of patients undergoing bypass surgery. Because the organized red clot preferentially absorbs the green argon laser light, laser angioplasty may be the best method for opening these grafts in the future. However, conventional PTCA should be adequate, quicker, and easier for subtotal occlusions. If the laser procedure is successful, the cost is much less than that of CABG and hospitalization may be shortened to two days. This trial was not a prospective, double-blind, randomized, controlled clinical investigation and will require further research. Mark Murphy, MD hypertension, nifedipine, clonidine

Oral n i f e d i p i n e v e r s u s oral c l o n i d i n e in t h e t r e a t m e n t of u r g e n t h y p e r t e n s i o n Jaker M, Atkin S, Soto M, et al Arch Intern Med 149:260-264 Feb 1989

This randomized, double-blind, prospective,study investigated the effectiveness of oral nifedipine or clonidine in lowering the blood pressure of hypertensive adults. Fiftyone patients (mean age, 48.2 years) with diastolic blood pressures of 129 m m Hg or more were treated with either 20 mg nifedipine or an initial dose of 0.2 mg clonidine followed by 0.1 mg hourly for up to six hours. Mean initial blood pressure on the nifedipine group was 210/130 mm Hg. All patients who received nifedipine experienced a reduction in diastolic blood pressure (DBP) of 20 m m Hg or more. Nifedipine reduced the DBP to less than 110 rnm Hg in 83% of the patients within 45 minutes and in 96% within 120 minutes. Thirty percent of the patients experienced a subsequent increase in DBP to more than 120 mm Hg by 150 minutes. No clinically significant side effects were noted in this patient population. In the clonidinetreated group, the mean initial blood pressure was 206/132 m m Hg. Clonidine reduced the DBP in 79% of patients to

Annals of Emergency Medicine

18:10 October 1989