Alan K. Banks

Anomalous origin and course of coronary arteries in adults: Identification and improved imaging utilizing transesophageal echocardiography

Anomalous origin of a coronary artery is rare, but may represent a clinically significant abnormality, since some anomalies are associated with myocardial ischemia, infarction, and sudden death. Diagnosis may elude routine screening procedures, and even when an anomalous vessel is identified angiographically, it may be difficult to delineate its true course on the basis of angiography alone. The purpose of this study was to determine whether transesophageal echocardiography (TEE) is of value in making the diagnosis and outlining the course of anomalous coronary arteries. Five adult patients with anomalous origin of a coronary artery were studied by monoplane TEE and selective coronary angiography. Transthoracic echocardiography (TTE) was also performed in four of these five patients. Anomalous coronary ostia were visualized in four of five patients utilizing TEE, but in none of four patients by TTE. A proximal segment of the anomalous coronary vessel was identified in all five patients by TEE, and in only two of four patients by TTE. TEE images were consistently of superior diagnostic quality. TEE is a valuable tool for the echocardiographic identification of anomalous coronary arteries, and is superior to TTE in adult patients.

A new balloon-expandable tantalum coil stent: Angiographic patency and histologic findings in an atherogenic swine model

The angiographic patency and histologic characteristics of a new balloon-expandable tantalum stent were studied after implantation intervals ranging from 1 to 32 weeks in atherogenic miniature swine peripheral and coronary arteries. Stents were placed in 34 arteries (10 coronary and 24 iliac arteries) in a total of 13 swine. Two swine died within 24 h of stent implantation. Follow-up angiography was performed before death was induced in 11 swine (8 coronary and 19 iliac arteries) and revealed 100% patency without evidence of lumen stenosis, thrombosis or migration of the stents. The neointimal thickening was maximal at 4 weeks after stent implantation and was at its minimum at 32 weeks after implantation with reendothelialization of the stents generally complete at that time. An advantage of this balloon-expandable device is its inherent longitudinal flexibility. The coil configuration allowed the nondeployed stent to negotiate acute bends in coronary arteries to reach the site of implantation and also allowed the deployed stent to conform to the natural contour of tortuous coronary arteries. The tantalum device was remarkable for its radiographic visibility, which greatly aided its placement under fluoroscopic guidance. This study demonstrates this stents ease of implantation, excellent patency rate and absence of restenosis due to neointimal proliferation for up to 8 months in this atherogenic swine model.

Post-atherectomy coronary artery aneurysm

A 52-year-old man underwent an uneventful directional atherectomy of the left anterior descending coronary artery. Four months after the procedure unstable angina developed and on angiogram an aneurysm of the left anterior descending coronary artery was noted. The patient underwent bypass of the left anterior descending coronary artery. An attempt to exclude the aneurysm resulted in hemodynamic compromise and was discontinued. Follow-up angiogram 2 months after operation showed the aneurysm to be smaller. The patient is doing well 6 months after operation.

Optical properties of fiber optic surgical tips.

The optical emission pattern of experimental sphere-tipped fibers and an assortment of shapes of sapphire-tipped fibers has been measured. The emission patterns were recorded in both air and water. These patterns show that cone and wedge shaped tips unexpectedly have focusing properties. The observed patterns help give an understanding of the results that the tips produce on tissues. The optical analysis suggests ways of improving tip designs.

Fatal esorubicin-induced cardiomyopathy: report of a case and review of the literature

SummaryA case of fatal dilated cardiomyopathy induced by esorubicin (ESO) at a total dose of 740 mg/m2, given in 27 doses over 650 days, is reported. The sudden onset, rapid clinical deterioration, and fatal outcome are detailed. The outcome was not predicted by serial rest ejection fractions or clinical signs. The data from animal studies, phase 1 and phase 2 clinical testing, are reviewed, demonstrating the almost complete absence of reports of ESO-induced cardiotoxicity. Studies reviewing ejection fractions and myocardial biopsy scores show that ESO can be cardiotoxic and may produce fatal dilated cardiomyopathy.

Tolerance of normal aorta to oversized dual balloon valvuloplasty. Observations in a swine model: Technical note

The damage threshold during aortic valvuloplasty was determined in 12 normal swine subjected to inflation of oversized dual balloons. Catheters with combined balloon diameters of 1.2–2.0 times the aortic annulus were selected. Following completion of the procedure, the animals were sacrificed and examined for pathology. With combined balloon diameters less than or equal to 1.7 times the aortic annulus, there was no gross, or microscopic damage. In animals with combined diameters equal to 2 times the aortic annulus, there was rupture of the aorta. This data provides further basis for the selection of catheter sizes in dual balloon aortic valvuloplasty.

Percutaneous transluminal coronary angioplasty guidewire-induced coronary artery dissection without balloon inflation

A case of arterial dissection of the right coronary artery secondary to angioplasty guidewire manipulation is presented. No balloon inflation was performed. The histologic appearance of the involved arterial segment was similar to that found in the left anterior descending coronary artery, which had undergone successful balloon dilatation. Both arteries demonstrated medial disruption and fibrointimal proliferation. The pathologic features of angioplasty-induced vascular injury may occur with or without balloon inflation.

Modified Fiber Tip Laser Angioplasty In An Atherosclerotic Swine Model.

Laser angioplasty of atherosclerotic iliac arteries of Yucatan miniature swine was performed with an argon laser source coupled to a 200 gm silica quartz fiber with 1.0 mm, 1.2 mm, or 1.5 mm silica ball-tips fused to the distal end of the fiber. After initially failing to cross the lesion with a guide wire, laser angioplasty was attempted in 41 lesions in 22 animals. The laser energy was delivered with the ball-tip in contact with the lesion in 1 to 5 second pulses at a mean power of (±SD) of 2.9 ± 0.2 watts. The average energy delivered per pulse was 8.6 ± 3.7 joules for 7.9 ± 6.5 pulses per lesion. Successful recanalization was determined angiographically. Following laser recanalization balloon angioplasty was attempted to further improve the lumen size. Successful laser recanalization was observed in 35 of 41 (85%) lesions and laser-induced perforation occurred in 5 (12%). No instances of mechanical perforation occurred due to the atraumatic, blunt nature of the ball-tip laser fiber. Laser angioplasty with this modified fiber tip is an effective method for recanalizing obstructed arteries which otherwise would not be amenable to balloon angioplasty.

Laser Transmission Characteristics In Blood-Saline Solutions.

Studies were made of the propagation of both continuous wave, all line, argon ion (515,496,488,476 nm) and Nd:YAG (1060 nm) laser radiation from a spherically-tipped optical fiber through a blood-saline solution. It was found that the transmission of the argon ion laser light through the mixture increased as the power emitted from the tip increased. The transmission of Nd:YAG laser radiation through a similar mixture showed a reduction in transmission as power increased.