Development of a sensitive PCR-dot blot assay to supplement serological tests for diagnosing Lyme disease.

Laboratory diagnosis of Lyme disease is difficult and presently dependent on detecting Borrelia burgdorferi-specific antibodies in patient serum with the disadvantage that the immune response to B. burgdorferi can be weak or variable, or alternatively, the slow and inefficient culture confirmation of B. burgdorferi. PCR tests have previously shown poor sensitivity and are not routinely used for diagnosis. We developed a sensitive and specific Lyme Multiplex PCR-dot blot assay (LM-PCR assay) applicable to blood and urine samples to supplement western blot (WB) serological tests for detecting B. burgdorferi infection. The LM-PCR assay utilizes specific DNA hybridization to purify B. burgdorferi DNA followed by PCR amplification of p66 [corrected] and OspA gene fragments and their detection by southern dot blots. Results of the assay on 107 and 402 clinical samples from patients with suspected Lyme disease from Houston, Texas or received at the IGeneX laboratory in Palo Alto, California, respectively, were analyzed together with WB findings. The LM-PCR assay was highly specific for B. burgdorferi. In the Texas samples, 23 (21.5%) patients antibody-negative in WB assays by current US Centers for Disease Control (CDC) recommended criteria were positive by LM-PCR performed on urine, serum or whole blood samples. With IGeneX samples, of the 402 LM-PCR positive blood samples, only 70 met the CDC criteria for positive WBs, while 236 met IGeneX criteria for positive WB. Use of the LM-PCR assay and optimization of current CDC serological criteria can improve the diagnosis of Lyme disease.

Predictors of mortality in end-stage renal disease patients with mitral annulus calcification.

OBJECTIVE: Mitral annulus calcification (MAC) is an independent predictor of cardiovascular mortality in the general population. The purpose of the current historical cohort study is to assess risk factors for long-term mortality in end-stage renal disease (ESRD) patients with MAC (n = 30; age, 62 +/- 2 yr), as compared to ESRD patients without MAC (n = 30; age, 63 +/- 2 yr). Additional analysis compared ESRD patients with MAC to non-ESRD patients with MAC (n = 32; age, 66 +/- 2 yr). METHODS: The groups included age-matched male patients followed at a single center. Long-term survival was assessed by Kaplan-Meier analysis. Regular and stepwise Cox proportional hazards models were used to determine risk factors for mortality. RESULTS: There was a similarly high prevalence of cardiovascular complications, including hypertension, coronary artery disease, left ventricular hypertrophy, atrial fibrillation, and congestive heart failure, in all three groups. Median survival time was significantly longer in non-ESRD patients (90 months), compared with the ESRD with MAC (45 months) and ESRD without MAC (45 months) patients (log-rank test; P < 0.001). With stepwise Cox proportional hazards model, including ESRD patients with MAC and ESRD patients without MAC, increased calcium x phosphate product, decreased serum creatinine concentration, and the presence of coronary artery disease and lower extremity amputations were independent predictors of mortality for patients with ESRD. With stepwise Cox proportional hazards model, including ESRD patients with MAC and non-ESRD patients with MAC, the presence of ESRD, atrial fibrillation, diabetes, aortic valve calcification, coronary artery disease, and tricuspid regurgitation were independent predictors of mortality. CONCLUSION: The mortality rate was high in ESRD patients, approximately 15% per year. After accounting for baseline cardiovascular disease and traditional risk factors, the presence of MAC did not confer additional risk for mortality.

Two-dimensional echocardiography in cardiac tamponade occurring after cardiac surgery.

Cardiac tamponade is an important complication after cardiac surgery, yet little has been published on the echocardiographic diagnosis of this situation. The two-dimensional echocardiograms of 11 patients who required surgical relief of cardiac tamponade complicating cardiac surgery were therefore reviewed. Four had nonloculated pericardial effusions surrounding both ventricles. The other seven patients had a loculated posterior pericardial effusion; in three of these the effusion altered left ventricular posterior wall contour so that it was concave toward the effusion in the long-axis view; in two, a strikingly abnormal motion of the left ventricular posterior wall was noted, such that the width of the posterior pericardial space diminished in systole and widened abruptly in early diastole. The quantity of pericardial contents (fluid, blood or clot) evacuated surgically was smaller than usually encountered in patients with tamponade due to various "medical" conditions. Thus, unlike tamponade with other pericardial effusions, tamponade after cardiac surgery is due to a pericardial effusion that is smaller in volume, often loculated posteriorly and associated with certain unique two-dimensional echocardiographic features.

Abnormalities in the mitral valve apparatus in patients undergoing long-term hemodialysis. Autopsy and echocardiographic correlation.

Examination of the heart at autopsy in patients who received long-term hemodialysis revealed the following two changes in the mitral valve apparatus previously almost completely overlooked: (1) fibrosis and thickening affecting chordae tendineae in four cases: in one, severe mitral regurgitation was documented by hemodynamic studies; (2) extensive calcification in the mitral anulus region in two cases, with calcification in the base of the mitral leaflets in one and in the papillary muscle and chordae tendineae in the other. The causes of these abnormalities is unclear. Rheumatic and other known causes all seem unlikely origins of the extensive fibrosis. Secondary hyperparathyroidism is probably responsible for the calcification. In all six patients, these abnormalities in the mitral valve apparatus, which may be associated with functional impairment, were diagnosed during life by M-mode and two-dimensional echocardiography.

Echocardiographic detection of cardiac involvement in patients with chronic renal failure.

Echocardiography was performed in 50 patients in chronic renal failure with symptoms suggestive of possible cardiac involvement. Pericardial effusions were detected in 33 and pericardial thickening in 22. In five patients solid material, probably fibrinous, was seen adherent to the parietal or visceral pericardium. The left ventricle was dilated in 18 patients and showed definitely impaired contractility in 16. The left ventricular (LV) posterior wall was abnormally thick in 19 patients. In two, the ventricular septum was more than 1.3 times as thick as the LV posterior wall. Other echocardiographic findings included calcification in the mitral annulus region, mitral valve vegetations, and thickened chordae tendineae. Echocardiography has proved to be of great help in the assessment of symptomatic patients with chronic renal failure not only in diagnosing the presence and extent of pericardial effusion and thickening, but also in detecting impaired myocardial contractility, calcification in the posterior mitral annulus region, and vegetations of bacterial endocarditis.

Echocardiographic practice in a large metropolitan area.

A survey performed concerning echocardiography in a metropolitan area. Of 110 hospitals in the area, 62 reported having echocardiographic facilities. Echocardiographic physicians and/or technicians from 41 of these hospitals responded to questionnaires designed to determine the following: (1) educational background and credentials of technicians, (2) average salaries of technicians, (3) role of the physician and technician in the performance and reporting of echocardiograms, (4) volume, cost, and method of storage of echocardiograms, and (5) number and type of echocardiographic units in use. Our data suggest various trends, including a lack of formal training among technicians, the prevalence of cardiologists-internists as directors of echocardiographic facilities, the performance of echocardiograms by cardiology fellows in only 46% of institutions with cardiology training programs, and the widespread projected availability of cross-sectional echocardiographic capability within the next two years.

Submitral calcification or sclerosis in elderly patients: M mode and two dimensional echocardiography in "mitral anulus calcification".

Submitral calcification or sclerosis was visualized with M mode echocardiography in 84 elderly patients, 35 of whom were also studied with two dimensional echocardiography. Posterior submitral calcification, commonly referred to as "mitral anulus calcification," was present in 82 patients and was located in the angle between the posterior mitral leaflet and left ventricular posterior wall, rather than in the mitral anulus proper. M mode scans from the left ventricle to the left atrium showed that posterior submitral calcification ended abruptly in 66 cases, and in these it became contiguous with the posterior atrioventricular junction (true mitral anulus) in only 14 instances, in 16 patients the posterior submitral calcification sloped anteriorly to merge with the posterior aortic root. Anterior submitral calcification was visualized in 12 patients, 10 of whom also had posterior submitral calcification. Anterior submitral calcification was usually located immediately anterior to the base of the anterior mitral cusp. In two cases, if appeared to arise in the region between the aortic and mitral rings; in one instance, it was located in the mid left ventricle, in the mitral chordal region. We suggest that the terms anterior and posterior submitral calcification are more appropriate than "mitral anulus calcification" because in most cases such calcific deposits do not appear to be located in or to arise from the true mitral anulus.

Dynamic cyclic changes in coronary sinus caliber in patients with and without congestive heart failure.

M-mode echography of the coronary sinus in the apical 2-chamber view enabled us to measure coronary sinus caliber at specific phases of the cardiac cycle. Coronary sinus narrowing occurs consistently during atrial contraction, but is always absent in atrial fibrillation; in patients with congestive heart failure and systemic venous congestion, this narrowing is significantly attenuated.

Echocardiographic simulation of pericardial fluid accumulation by right pleural effusion.

On two-dimensional echocardiography, in the subcostal four-chamber view, right pleural effusion can present as a large echo-free space adjacent to the echo-free space representing the right atrium, thus simulating a loculated pericardial effusion or a pericardial cyst. On occasion, the echo-free space representing the right pleural effusion can bulge into the right atrium, distorting the right atrial shape, and thereby produce an echocardiographic appearance that may be confused with an indentation of the right atrial wall by pericardial effusion. The latter has recently been described as a sign of pericardial tamponade.

Echocardiographic simulation of pericardial effusion by ascites.

Subcostal echocardiography in patients with tense ascites can reveal an echo-free space anterior to the heart which could be mistaken for a loculated anterior pericardial effusion or a pericardial cyst. The ascitic nature of the space can be recognized by the contours of the space, its relationship to the liver, and to the distinctive midline appearance of the falciform ligament of the peritoneum bisecting the space. Less frequently ascitic fluid inferior to the left ventricle, between it and an enlarged spleen, can mimic a posterior pericardial effusion, on M-mode and even long-axis 2-D echography, but the ascitic nature of the space is evident on the short-axis 2-D view.

Noninvasive imaging of a retrocardiac spleen. Unusual component of paraesophageal diaphragmatic hernia.

The findings on chest roentgenograms, cardiac ultrasound, computed tomography (CT), and radionuclide liver-spleen scan are described in a 54-year-old man with a paraesophageal diaphragmatic hernia. The CT revealed the spleen as a solid mass with a notched border adjacent to the intrathoracic retrocardiac stomach. The radionuclide scan showed splenic uptake above the diaphragm. The diagnosis in this case, which, to our knowledge, is the first such reported case, was confirmed at surgery.

Echocardiographic features of second degree atrioventricular block.

Echocardiographic studies demonstrated abnormalities of motion of the pulmonary valve, the aortic root and valve, the mitral and tricuspid valves, the left ventricle, and the left atrium in two patients with second-degree atrioventricular block. During Wenckebach 3:2 atrioventricular conduction, ventricular beats exhibited alternately long and short periods of systolic opening of the pulmonary and aortic valves and alternately large and small left ventricular stroke volumes. During 4:3 and 3:2 Wenckebach atrioventricular conduction, the left ventricular stroke volume was directly proportional to the preceding end-diastolic volume. During 2:1 atrioventricular conduction, the blocked atrial contractions may produce movements of the left atrial wall, thereby revealing the true atrial rate when the blocked P waves are obscured in the electrocardiogram by their superimposition on preceding T waves.

Ultrasound visualization of aortic dissection by right parasternal scanning, including systolic flutter of the intimal flap.

Dilation of the ascending aorta and an intimal flap within it (indicating dissecting aneurysm) were visualized by M-mode and cross-sectional echocardiography, from the right but not from the left parasternal area. The diagnosis was confirmed by aortography and at surgery. Systolic flutter of the intimal flap, seen on M-mode echocardiography, was attributable to the jet from a mildly stenotic aortic valve impinging on it.

Noninvasive diagnosis of right cervical aortic arch.

A two-year old asymptomatic boy presented with a systolic right supraclavicular thrill. Two-D echography revealed a pulsating loop of tubular echo-free space at this site. Barium esophagogram showed a large curved retroesophageal impression. A noninvasive diagnosis of right cervical aortic arch with left descending aorta can be made on the basis of this combination of findings.

Pulsus alternans with alternation of mitral flow and motion patterns.

A 41-year-old man with dilated cardiomyopathy had persistent pulsus alternans on physical examination and on cardiac catheterization. On M-mode echocardiography patterns of mitral valve diastolic motion showed alternation such that the E phase was longer and the A phase shorter after stronger ventricular contractions. At faster rates the A peak was apparently absent in alternate diastoles. Doppler recordings of mitral flow exhibited alternation such that the peak velocity and duration of early diastolic flow were larger after stronger ventricular contractions; diastolic mitral regurgitation was noted only in such (alternate) diastoles.

Mitral valve prolapse and stroke: echocardiographic evidence for a missing causative link.

There is general acceptance of a causal connection between mitral valve prolapse and systemic embolic events. The precise mechanism, however, remains controversial, with current hypotheses favoring the embolization of thrombotic deposits from the abnormal mitral valve. It might be surmised that echocardiography could easily document the presence of such thrombi, but actually, this has never been reported previously. Described herein is a patient with a severe cerebrovascular accident in whom echocardiography clearly demonstrated a mass of high embolic potential attached directly to the prolapsing mitral valve leaflet.

Differences in the shape of the normal, cardiomyopathic, and volume overloaded human left ventricle.

A transformation from the normal elliptical shape of the left ventricle that may accompany various disease states and that may be indicative of myocardial remodeling, has not been completely addressed in part because of the need for a descriptor of shape that is independent of chamber size. Accordingly, the goal of this study was twofold: to derive dimensionless echocardiographic descriptors of left ventricle chamber shape that are independent of chamber volume and to use these descriptors to quantitatively compare the shape of left ventricles that were either of normal size (81 +/- 17 ml, 19 patients) or were enlarged secondary to idiopathic cardiomyopathy (194 +/- 61 ml, 46 patients) or chronic aortic or mitral valve incompetence (196 +/- 67 ml, 14 patients). Two-dimensional and M-mode determined descriptors of left ventricle shape based on its width, length, and area were found to be independent of left ventricle volume. These descriptors were significantly greater in cardiomyopathy compared with the normal or dilated left ventricle secondary to valvular incompetence, indicating that the left ventricle had become nearly spherical. A spherical shape of the left ventricle was not observed with valvular incompetence. The ability to classify a patient as having either a normal or a cardiomyopathic left ventricle by discriminant function analysis was enhanced when both left ventricle size and shape were considered. In a prospective study using discriminant function and fractional shortening, we found that patients with valvular incompetence could be classified as having either a normal discriminant function and fractional shortening, an abnormal discriminant function and normal fractional shortening, or an abnormal discriminant function and fractional shortening.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary artery disease, myocardial infarction, and brain embolism.

The incidence of in-hospital stroke complicating acute myocardial infarction is approximately 1%. This rate is largely unaffected by thrombolytic therapy. Large myocardial infarctions, anterior wall involvement, prior stroke, and increasing age are risk factors for ischemic stroke. Left ventricular thrombi commonly occur with anterior wall infarctions. There is some evidence that anticoagulation reduces their incidence and uncontrolled studies suggest that anticoagulation may reduce the risk of embolization. Left ventricular aneurysms have a low rate of embolization and do not require systemic anticoagulation. Treatment of acute myocardial infarction with t-PA and anisoylated plasminogen streptokinase activator complex are associated with a higher risk of stroke than treatment with streptokinase; this excess risk is attributable to an increased rate of cerebral hemorrhages.

Pericardial metastasis from testicular seminoma: appearance and disappearance by echocardiography.

At the time of initial diagnosis, testicular malignancy is usually limited to the testicle and infradiaphragmatic lymph nodes. Metastases initially follow the retroperitoneal lymph channels and subsequently extend to the supradiphragmatic lymph nodes in the mediastinum and supraclavicular fossa. Testicular metastases to the pericardium are rare and usually asymptomatic. These lesions are most commonly identified at autopsy; therefore, the actual incidence is unknown. The authors report a 32-year-old man with testicular carcinoma, who developed asymptomatic pericardial metastases without concomitant supradiaphragmatic nodal or pulmonary metastases. They review the efficacy of echocardiography in diagnosis and follow up or pericardial metastasis.

Thromboembolization complicating left ventricular pseudoaneurysm: serial two-dimensional and color-flow Doppler echocardiographic observations.

A left ventricular pseudoaneurysm was diagnosed by two-dimensional echocardiography and color-flow Doppler imaging, and confirmed by computerized tomography and angiocardiography, in a man with known coronary disease who had had recent recurrent systemic emboli. A thrombus within the pseudoaneurysm was visualized, and its disappearance on serial echocardiograms coincided with the occurrence of embolization to the aortic bifurcation.