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O Topaz

Publications and source records attributed to O Topaz.

At least 55 records · Page 3Linked to original sources
PubMed1995

Laser-assisted coronary angioplasty in patients with severely depressed left ventricular function: quantitative coronary angiography and clinical results.

Laser-assisted coronary angioplasty can be successfully applied to lesions not ideal for balloon angioplasty. Patients with severely impaired left ventricular (LV) function and complex coronary artery stenoses who call for percutaneous revascularization are considered a high risk group for balloon angioplasty. In order to determine the feasibility, safety, and acute clinical outcome of a solid state, pulsed wave, mid-infrared (2.1 micron) laser facilitated angioplasty in these patients, data from 112 patients with 129 lesions were analyzed. Patients were identified according to angiographic LV function; group I included 22 patients with left ventricular ejection fraction (LVEF) < or = 40% (mean = 25% +/- 10%) and group II included 90 patients with LVEF > or = 40% (mean = 58% +/- 8%). No difference in age, gender, diabetes, hypertension, tobacco use, history of previous coronary artery bypass surgery (CABGS) or percutaneous transluminal coronary angioplasty was registered between the two groups. Multivessel disease, previous myocardial infarction (MI), and severe angina were more prevalent among group I patients (P = 0.03). No difference was found in lesion location, complexity, length, or calcification between the two groups; although group I had more eccentric lesions. Both groups were treated with the same laser energy level followed by adjunctive balloon angioplasty. One hundred percent procedural success was obtained in group I versus 93% in group II (P = NS). By Q.C.A. (independent core lab), minimal luminol diameter increased in group I from 0.9 +/- 0.5 mm preprocedure to 2.0 +/- 0.5, as compared to 0.8 +/- 0.5 mm to 1.9 +/- 0.5 mm (P = NS) in group II. Stenosis severity improved from 69% +/- 16% preprocedure to 37% +/- 13% postprocedure in group I, as compared to improvement from 78% +/- 16% to 37% +/- 12.7% in group II (P = NS). Overall complication rate was remarkably low, with no death or perforation in either group; emergency CABGS 0% in group I and 1.1% in group II; dissections 4.5% in group I and 8.8% in group II. There was no significant difference in complication rate between the two groups. The results of this study suggest that holmium:YAG laser facilitated coronary angioplasty can be safely performed in patients with severe LV dysfunction, achieving a remarkably high procedural success and low complication rate.

Aged↗
PubMed1993

Laser facilitated angioplasty and thrombolysis in acute myocardial infarction complicated by prolonged or recurrent chest pain.

To date, application of laser angioplasty in acute myocardial infarction (MI) has not been reported. In nine patients with acute myocardial infarction complicated by continuous or recurrent severe ischemia and chest pain, a mid-infrared, solid-state, pulse-wave holmium/thulium:YAG coronary laser was applied. In six of these patients the laser was specifically utilized for the purpose of coronary thrombolysis. In each case a guidewire was placed across the stenosis and a multifiber laser catheter was utilized, emitting 250-600 mJ/pulse at 5 Hz, followed by adjunctive balloon angioplasty. Laser success (defined as ability to cross the lesion, reduction of > or = 20% in stenosis and thrombolysis when a thrombus is present) was achieved in all patients. Final angiograms revealed residual stenosis < or = 30%, adequate thrombolysis and no major complication (MI, perforation, emergency CABGS, CVA, death) in each patient. Clinically, all nine patients improved, survived the acute infarction and were discharged. This initial clinical experience demonstrates the feasibility and safety of holmium/thulium:YAG laser application in thrombolysis and plaque ablation in selected patients who experience acute myocardial infarction complicated by prolonged or recurrent ischemia and chest pain.

Adult↗
PubMed1993

Balloon catheter systems for PTCA: the importance of the catheter length.

The length of a balloon catheter system plays an important role in successfully dilating distal coronary or vein graft stenoses. We herein report a case in which a distal saphenous vein graft lesion could not be reached with a conventional balloon catheter. Factors responsible for this failure included insufficient length. The lesion was eventually reached and successfully dilated with another balloon catheter, which according to the manufacturer had the same length as the first balloon. In order to study this phenomenon eleven balloon catheters were examined using the following measurements: functional catheter length, deliverable catheter length, crossing distance and longitudinal compression. Seven guide catheters were also measured. Results showed variations in standard functional length between several manufacturers, ranging from 132.2-137.8 cm. The deliverable length ranged from 18.3-23.9 cm, crossing distance ranged from 7-37 mm, and the longitudinal compression ranged from 4-30 mm. Guiding catheter length varied among several manufacturers, ranging from 100.6-107 cm. A significant variation was found not only among certain manufacturers, but also among several standard catheters made by one manufacturer. The results of this study suggest that significant variations exist in the length of standard balloon catheters and guiding catheters even among those made by the same manufacturer. These findings can affect the ability to reach a lesion and should be taken into account, especially when attempting to perform angioplasty of stenoses located in the distal portion of a coronary artery or saphenous vein graft.

Aged↗
PubMed1993

Observations of angina and myocardial infarction in constrictive pericarditis.

The common symptoms of constrictive pericarditis, i.e. dyspnea on exertion, shortness of breath and cough, relate to impairment of ventricular filling and to a progressive rise in systemic and pulmonary venous pressures. Myocardial ischemia, angina and myocardial infarction are rarely associated with this disease. We have encountered two patients with constrictive pericarditis, one presenting with angina and the other with acute anterior wall infarction. Possible etiologies of constrictive pericarditis in the first case include cardiac surgery, chronic renal failure and myocarditis; in the second case, Crohn's disease. The proposed mechanism of chest pain in the first patient was a reduced cardiac output resulting in underperfusion of the coronary arteries, although it is possible that the patient experienced angina due to the presence of severe coronary artery disease. In the second patient an anterior wall infarction and post-infarction angina were attributed to obliteration of the left anterior descending artery by constraint of a thickened pericardium. In both cases non-invasive imaging modalities were not of use in establishing the diagnosis of constrictive pericarditis. Clinical awareness and accurate hemodynamic measurements continue to play a key role in the diagnostic process.

Angina Pectoris↗
PubMed1993

A new, safer lasing technique for laser-facilitated coronary angioplasty.

In vitro studies during cold pulsed-wave laser angioplasty have demonstrated production of gas bubbles within the target tissue, creation of shock wave and formation of multi-layer dissections accompanied by an increase in the plaque and vessel wall temperature. These processes account for certain complications of coronary lasing, including acute vessel closure, dissections, spasm, and even perforation. The traditional lasing technique in which a large number of pulses is continually emitted across the lesion, may in fact contribute to the development and acceleration of the above mentioned processes. To overcome the shortcomings we have developed a new, safe lasing technique that consists of multiple trains of a small number of pulses each. Between laser sessions the laser catheter is retracted into the guiding catheter and nitroglycerin is injected intracoronary, thus providing time for dispersion of produced gas bubbles, cooling of the target artery, and adequate coronary vasodilatation. This new technique results in a significant reduction of laser associated complications.

Adult↗
PubMed1993

Septal perforator artery angioplasty: the advantage of application of an ultralow-profile balloon system--a case history.

Coronary artery disease can affect the septal perforator arteries and cause clinical sequelae, including angina, infarction of the interventricular septum, arrhythmias, and congestive heart failure. However, the size and the course of the septal perforator arteries significantly differ from those of the major epicardial coronary vessels. These anatomic features present certain technical challenges for angioplasty of the septal arteries. This case demonstrates that application of an ultralow-profile balloon-over-the-wire system can meet the specific requirements of septal artery angioplasty and achieve adequate results.

Aged↗
PubMed1992

The Vineberg procedure revisited: angiographic evaluation and coronary artery bypass surgery in a patient 21 years following bilateral internal mammary artery implantation.

A patient receiving bilateral internal mammary implantation (Vineberg's operation) in 1969 was symptom free for a period of 21 years. In 1990 he developed acute myocardial infarction followed by post-infarction angina. Cardiac catheterization revealed severe left main and three vessel disease and patency of both mammary implants which filled the left anterior descending and circumflex coronary arteries via collaterals. Coronary artery bypass surgery was indicated due to the native coronary artery disease and inability of the internal mammary grafts' blood flow to alleviate symptoms. The patient underwent direct coronary artery bypass grafting utilizing femoral vessels for cannulation and saphenous veins for grafting, while preserving the mammary implants. This unique case attests to the longevity of the internal mammary artery grafts. These grafts, even if directly implanted, can serve as a crucial source of blood to an otherwise severely underperfused myocardium. Strategy and technical aspects of surgical redo in patients who underwent Vineberg's operation are discussed.

Aged↗
PubMed1992

Coronary perforation during angioplasty: angiographic detection and demonstration of complete healing.

A patient is presented with localized perforation of the left anterior descending artery secondary to angioplasty balloon rupture. Despite a remarkable angiographic picture of coronary tear and dye extravasation into the surrounding pericardial tissue, the patient remained hemodynamically stable, and was medically treated. Five years later she redeveloped angina, and repeated coronary arteriography revealed complete healing of the perforation site. This case attests to the remarkable ability of the coronary artery to completely heal from a major wall trauma. Although a rare complication of coronary angioplasty, perforation can occur, and various management aspects should be considered.

Aged↗
PubMed1992

Interventricular septal rupture complicating acute myocardial infarction: from pathophysiologic features to the role of invasive and noninvasive diagnostic modalities in current management.

Rupture of the interventricular septum is a serious complication of acute myocardial infarction, accounting for 5% of deaths due to acute infarction. The septal perforation most frequently occurs during the first week after the infarction. The majority of these patients present with at least two-vessel coronary artery disease, and most cases have a total occlusion of the infarct-related artery. The degree of associated right ventricular damage is clinically important. Unpredictable hemodynamic deterioration can rapidly develop in 80% of the patients, and mortality with medical therapy alone exceeds 90%. Because the preoperative hemodynamic status of these patients appears to be a major determinant for survival, accurate diagnosis, urgent management, and early operative correction are necessary to avoid a catastrophic clinical outcome. Traditionally, diagnostic procedures included first, the insertion of a pulmonary artery catheter for recording of pressures, sequential oximetry, and calculation of the shunt's magnitude and the cardiac output followed by left ventriculography and coronary arteriography for angiographic demonstration of the shunt and the coronary anatomy. Currently, optimal utilization of color flow Doppler and two-dimensional and transesophageal echocardiography offers a significant clinical advantage and can be used to shorten the time spent on diagnosis, evaluation, and management prior to the urgent surgical repair. The elimination of time-consuming diagnostic tests can contribute to further improvement in the survival rate.

Cardiac Catheterization↗
PubMed1992

Anomalous coronary arteries: angiographic findings in 80 patients.

Among 13010 adults who underwent coronary arteriography, 80 (0.61%) patients had a total of 83 anomalous coronary arteries. Thirty-three (41%) of the patients were of Hispanic origin, while out of the entire population studied 30% were Hispanic. The right coronary artery was the most common anomalous vessel. It was identified in 50 (62%) patients, arising in 35 from the left aortic sinus, in 14 from the posterior sinus, and in 1 from the left coronary artery. An anomalous circumflex artery was recognized in 22 (27%) patients. Nine (11%) patients presented an anomalous left anterior descending artery, 1 patient an anomalous left main coronary artery, and another an anomalous septal perforator artery. Twenty-three (29%) patients had concomitant congenital heart abnormalities, most commonly. bicuspid aortic valve and mitral valve prolapse. In each of 5 patients with complex congenital heart disease the course of the anomalous vessel could have interfered with a surgical procedure. In 4 cases anomalous coronary arteries were associated with either anomalous systemic venous circulation or anomalous cardiac veins. In 5 (6%) patients only, the anomalous coronary artery was solely responsible for a clinical event. Coronary atherosclerosis of the anomalous arteries was found in 28% of the patients, while the overall incidence of the disease in this series was 65%. Thus, anomalous coronary arteries are associated with a high incidence of congenital heart diseases, but do not appear to be associated with an increased risk for development of coronary atherosclerosis. The angiographic recognition of these vessels is important in patients who undergo coronary angioplasty or cardiac surgery. Variations in the frequency of congenital coronary anomalies as reported herein may be attributed to a genetic background.

Abnormalities, Multiple↗
PubMed1992

Holmium laser coronary thrombolysis--a new treatment modality for revascularization in acute myocardial infarction: review.

Thrombolytic therapy has changed the approach to management of acute myocardial infarction (AMI). Although its therapeutic benefit has been well established, only about one-third of AMI patients receive lytics. In AMI patients for whom thrombolytics fail to achieve revascularization or for whom lytics are contraindicated, percutaneous transluminal coronary balloon angioplasty (PTCA) can be utilized. However, in a clinical setting of AMI PTCA is less successful and is associated with a higher complication rate than with PTCA for angina alone. This review details a novel application of laser angioplasty; in patients with AMI complicated by continuous chest pain and ischemia, a mid-infrared (2.1 micron) solid-state, pulsed-wave Holmium:YAG coronary laser (Eclipse, Palo Alto, CA) can be utilized for coronary thrombolysis and plaque ablation. In each patient the laser was applied after failure of a thrombolytic agent or when thrombolytics were contraindicated. We have gained experience with 13 lesions, 12 in a coronary artery and 1 in a vein graft. In each case a multifiber with laser catheter (1.4, 1.5, 1.7 or 2.0 mm) was advanced over a guide wire, emitting 250-600 mj/pulse at 5 Hz, followed by adjunctive PTCA. Clinical success (defined as less than or equal to 50% residual stenosis, adequate thrombolysis, no complications [including death, CVA, CABGs, dissection, perforation]) was achieved in all patients. All patients improved clinically, survived the AMI, and were discharged. This initial clinical experience demonstrates the feasibility and safety of Holmium:YAG coronary laser angioplasty in revascularization during AMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Laser↗
PubMed1992

Anomalous septal perforator artery: a source for supportive circulation in severe coronary artery disease--case reports.

Anomalous origin of a septal perforator artery is an infrequent angiographic finding. However, its recognition is important in patients with coronary artery disease in order to avoid misdiagnosis and consequent management mistake. In 2 patients, coronary arteriography demonstrated an anomalous septal perforator artery supplying significant blood flow to a myocardial region previously perfused by a severely obstructed major coronary vessel. It appears that an anomalous septal artery can serve as an important source for supportive circulation in severe coronary artery disease.

Aged↗
PubMed1991

Application of coronary angioplasty to the septal perforator arteries.

Significant coronary artery disease affecting the septal perforator arteries can cause anginal pain, rhythm disturbances, or septal infarction. However, since these vessels are usually inaccessible to coronary bypass surgery, there is a tendency among angiographers and angioplasters to overlook lesions of the septal perforator arteries. Our experience suggests that if medical treatment is not sufficient to treat clinical manifestations resulting from septal perforator disease, then coronary angioplasty can be considered a therapeutic alternative for revascularization. We herein present 11 patients who underwent coronary angioplasty of a major septal artery and discuss angiographic and technical aspects of the procedure.

Angina, Unstable↗
PubMed1991

Isolated significant left main coronary artery stenosis: angiographic, hemodynamic, and clinical findings in 16 patients.

Among 21,545 adult patients who underwent consecutive coronary angiography, 16 (0.07%) were found during their coronary arteriography to have a significant isolated stenotic lesion (luminal diameter narrowing of 50% or more) located at the left main coronary artery. The remaining major epicardial coronary arteries and their branches were free of disease. A strong predilection for the isolated lesion to occur at the ostium of the left main artery was found (12 patients). The most common presenting symptom was angina of less than 4 weeks' duration, although one third of the group was asymptomatic. Resting electrocardiograms were normal in 12 patients, while three patients had T wave inversion and another had nonspecific ST-T changes. Eleven patients exhibited severe stenosis, with eight having 70% to 89% stenosis and three having 90% to 95% stenosis. Five patients had 50% to 69% stenosis. No significant differences were found between patients with angina and patients without angina with respect to age, left ventricular end-diastolic pressure, left ventricular ejection fraction, and mean percent stenosis of the obstructive lesion. Despite the severity and the crucial location of the obstructive lesion, most patients with an isolated, significant left main stenosis appear to have a preserved left ventricular ejection fraction, normal wall motion, and no significant alteration of the left ventricular end-diastolic pressure.

Adult↗