Therapeutic Interventional Procedures Research Articles

Is Cardiac Catheterization Necessary in the Era of Echocardiography?

Definitive evaluation of cardiovascular disease is traditionally accomplished by cardiac catheterization. Advances in transthoracic and transesophageal Doppler echocardiography provides an accurate and cost-effective approach when compared to cardiac catheterization. Recent data suggests that for most adult patients with aortic or mitral valve disease, Doppler echocardiographic data enables the clinician to make the same decision reached with catheterization data. Echo and Doppler studies are useful in guiding certain therapeutic interventional procedures, and in the diagnosis of aortic dissection, mechanical complications of myocardial infarction, and in identifying aortic atheromas as a potential source of embolism. Future research will need to demonstrate that not only is echocardiography cost-effective, but that it will change the outcome of the patient.

Impact of the menopause on skeletal metabolism and osteoporotic syndromes

Evidence is rapidly acumulating that implicates calcium intake and genetic factors as important determinants of the variations in bone mass in many geographical areas as well as the loss of bone following the accumulation of peak bone mass. However, it has also been well established that the postmenopausal component of bone loss is one of the predominant factors contributing to increases in the ratio of the female/male risk of skeletal fractures after the sixth decade of life, and that vertebral bone loss can result from relatively mild changes in estrogen production and metabolism before the clinical menopause begins. Although estrogen use during early menopause prevents bone loss in the axial and appendicular skeleton in the majority of females, those estrogen-dependent mechanism(s) that initiate and perpetuate alterations in osteoclast-osteoblast interactions and bone remodeling are still ill-defined. Until the specific pathophysiological mechanisms have been defined, the informed physician should attempt to identify those peri- and postmenopausal patients at risk for more active bone turnover and rapid bone loss syndromes utilizing well-established and FDA-approved therapeutic interventional procedures to prevent the loss of skeletal tissue.

Analysis of data in idiographic research. Issues and methods.

Time-series and single-subject designs are being advocated for use in rehabilitation research to document the effectiveness of therapeutic intervention procedures. The argument is made that these designs are practitioner-oriented and practice-based. Acceptance and application of single-subject procedures by rehabilitation researchers will depend on the development of reliable and accurate methods of data analysis. Previous research suggests that traditional visual analysis of graphed data is unreliable and that quantitative supplements to visual analysis should be included in single-subject investigations. The advantages and limitations of two commonly advocated supplements to visual analysis are examined. The two supplemental procedures are the split-middle method of trend estimation and the resistant trend line. One advantage of the resistant trend line is that it does not make the assumption of a linear pattern in single-subject data. The argument is made that the resistant trend line is the preferred method and should be selected over the more commonly used split-middle method of trend estimation. The advantages and limitations of other quantitative procedures are briefly examined.

Failure or success of complex catheter-based interventional procedures assessed by intravascular ultrasound

Intravascular ultrasound provides high resolution cross-sectional images of vessel walls and may help to characterize atherosclerotic plaque morphology subtypes. This new imaging modality may have an important role in assessing the results of standard and investigational interventional therapeutic procedures. Four case histories of patients with coronary artery disease treated with different catheter-based therapies are presented. In each case, intravascular ultrasound added diagnostic information unobtainable from standard radiographic imaging techniques. These cases, involving PTCA (balloon dilatation), directional coronary atherectomy, high-speed rotational ablation, and balloon-expandable stent implantation, each represent an interesting example of procedure success or failure that could not be fully discerned without the use of intravascular ultrasound. Specifically, the distribution of intramural dissection, the presence and magnitude of intracoronary calcification, and morphologic patterns of intimal hyperplasia leading to restenosis, were accurately identified by ultrasound images. Thus intracoronary ultrasound imaging significantly enhances the understanding of failure modes, success, and complications after therapeutic interventions in patients with complex coronary disease.

Characterization of atherosclerotic lesions by intravascular ultrasound: Possible role in unstable coronary syndromes and in interventional therapeutic procedures

Characterization of atherosclerotic lesions by intravascular ultrasound: Possible role in unstable coronary syndromes and in interventional therapeutic procedures

Real-time intravascular ultrasound imaging in humans

The capability of obtaining cross-sectional, high resolution images of arteries with the use of ultrasound catheters has recently been demonstrated in animal studies. In this study the in vivo feasibility of intravascular ultrasound imaging in humans was evaluated. In 26 patients who had undergone diagnostic cardiac catheterization or iliofemoral arteriography, 1 of 3 different models of 20-MHz ultrasound catheters was advanced retrograde, into the iliac arteries and aorta or anterograde into the femoral arteries and real-time cross-sectional images of the arteries were obtained in all. In 10, the iliac arteries were normal and appeared circular and pulsatile with a 3-layered wall and crisply defined lumens. In 7 patients with nonobstructive plaques, the plaque was easily identified in the ultrasound image as a linear, bright, adynamic echo-dense structure. In 4 with obstructive disease in the iliac artery, the arterial lumen appeared irregular, bordered by a thickened, nonpulsatile wall. Variable grades of atheromatous abnormalities in the wall could be visualized. In all 5 patients with arteriographic evidence of obstructive disease of the femoral artery, intravascular ultrasound displayed reduced lumens and irregular borders with protruding high-intensity echoes in the wall. In all patients, the arterial lumen and the normal or abnormal wall were well visualized in the ultrasound images. There were no complications. This study thus demonstrates the feasibility of intravascular ultrasound imaging of arterial circulation in humans. With further improvements in catheter design and image quality, this imaging approach is likely to have a number of potential applications in the assessment of peripheral and coronary arterial diseases and in guiding interventional therapeutic procedures.

Controversies in Peripheral Vascular Intervention

Although many diagnostic and therapeutic angiographic and vascular interventional procedures were established by radiologists, recent data suggest that many are now performed solely by cardiologists or other nonradiologist specialists. In a review of survey results, the author addresses the issue of who should be performing peripheral vascular interventions. With the number of peripheral vascular interventions increasing every year, interventional radiologists should strive to maintain a strong position in the performance of these procedures in order to retain a significant share of referrals. The author suggests that the subspecialty of interventional radiology will be strengthened if dedicated, fully trained cardiovascular interventional radiologists are willing to be more involved in the admission and long-term care of patients. Increased cooperation among specialists, more involvement in development of instrumentation and techniques, and establishment of ethical marketing strategies are also suggested as effective measures for sustaining the subspecialty and improving patient care.

Effect of pulsed progressive fluoroscopy on reduction of radiation dose in the cardiac catheterization laboratory

The increased application of therapeutic interventional cardiology procedures is associated with increased radiation exposure to physicians, patients and technical personnel. New advances in imaging techniques have the potential for reducing radiation exposure. A progressive scanning video system with a standard vascular phantom has been shown to decrease entrance radiation exposure. The effect of this system on reducing actual radiation exposure to physicians and technicians was assessed from 1984 through 1987. During this time, progressive fluoroscopy was added sequentially to all four adult catheterization laboratories; no changes in shielding procedures were made.During this time, the case load per physician increased by 63% and the number of percutaneous transluminal coronary angioplasty procedures (a high radiation procedure) increased by 244%. Despite these increases in both case load and higher radiation procedures, the average radiation exposure per physician declined by 37%. During the same time, the radiation exposure for technicians decreased by 35%. Pulsed progressive fluoroscopy is effective for reducing radiation exposure to catheterization laboratory physicians and technical staff.

Antecedents of loneliness: a factorial analysis.

ABSTRACT Based on the content analysis of verbatim reports of loneliness experiences provided by 526 subjects, I developed a model of the antecedents of loneliness. Eight factors are subsumed under three clusters and are differentiated into 20 components. In addition to highlighting the sources of the subjective experience, the present study demonstrates the complexity of the loneliness phenomenon. The suggested model is helpful in examining the various conditions that give rise to the different experiences that people report and may be useful in designing therapeutic intervention procedures according to the individual needs of the lonely.

Diagnostic and therapeutic interventional gallbladder procedures.

Diagnostic and therapeutic interventional gallbladder procedures.

The Experience of Loneliness: A Tri-Level Model

Abstract Based on the content analysis of verbatim reports of loneliness accounts provided by 526 subjects, I developed a three-level model of the experience of loneliness. Ten factors are subsumed under four major elements and are differentiated into 23 components. In addition to demonstrating the complexity of loneliness, the present study also highlights the sources of the subjective experience and the varied accounts reported by so many writers. This model may be useful in designing therapeutic intervention procedures according to individual needs of the lonely and in examining the various conditions that give rise to the different experiences of loneliness that people report.

Percutaneous diagnostic and therapeutic interventional radiologic procedures in children: experience in 100 patients.

Diagnostic and therapeutic interventional radiologic procedures that provide many treatment options in adults are gaining acceptance in pediatric medicine. Diagnostic (69 patients) and therapeutic (31 patients) interventional experiences in 100 children are summarized, and the procedures of choice for various clinical problems are outlined. Procedures include percutaneous biopsy for benign and malignant diseases, transhepatic cholangiography and biliary drainage, genitourinary procedures (nephrostomy, stent placement, balloon dilation), aspiration of fluid for laboratory analysis, therapeutic drainage of abscesses and noninfected fluid collections, and percutaneous gastrostomy and gastroenterostomy. Diagnoses were accurate in 96% of cases, and therapeutic procedures were successful in 84% of patients, usually obviating operation. Complications occurred in six patients (6%); the most severe was hemoptysis causing respiratory distress. There was no procedure-related mortality. Interventional procedures have wide applications in pediatric patients.

Sonographically Guided Percutaneous Renal Interventional Procedures

THE INCREASING use of percutaneous aspiration techniques has led to a variety of alternatives to surgical procedures for patients with diagnostic problems relating to the kidney and perirenal areas. The accessibility of the genitourinary tract to ultrasound and the absence of radiation afforded by its use make ultrasound a desirable modality for a number of interventional procedures. Table 1 lists the spectrum of diagnostic and therapeutic interventional procedures performed under sonographic guidance at the Montefiore Medical Center from 1975 to May 1983. Renal Biopsy The kidney was one of the first organs to be selected for percutaneous biopsy. In the past 30 years, the superiority of percutaneous biopsy over open biopsy has been well established for its high yield and low morbidity.1Both ultrasonic and fluoroscopic localization techniques are considered equal in accuracy. Ultrasound is advantageous because it is a gross anatomic examination and does not depend on renal