Gary S. Mintz

Recognition and embolic potential of intraaortic atherosclerotic debris.

Atherosclerotic disease of the thoracic aorta is common in the elderly and patients with clinical coronary artery disease. Although embolization can occur from atherosclerotic debris within the thoracic aorta, it is not commonly considered in the differential diagnosis of the source of a systemic embolism. In the current study, the prevalence, clinical significance and embolic potential of intraaortic atherosclerotic debris as detected by transesophageal echocardiography was determined. Intraaortic atherosclerotic debris was identified in 38 (7%) of 556 patients undergoing transesophageal echocardiography. An embolic event occurred among 11 (31%) of the 36 study patients with intraaortic atherosclerotic debris. The incidence of an embolic event was higher when the debris was pedunculated and highly mobile (8 [73%] of 11 patients) than when it was layered and immobile (3 [12%] of 25 patients) (p less than 0.002). Among 15 patients undergoing an invasive procedure of the aorta, the incidence of embolism was 27%. In conclusion, in a patient with an embolic event, the thoracic aorta should be considered as a potential source. Transesophageal echocardiography can reliably detect intraaortic atherosclerotic debris, and when it is identified, an invasive aortic procedure should be avoided if possible.

Transesophageal echocardiographic recognition of subaortic complications in aortic valve endocarditis. Clinical and surgical implications.

BackgroundSecondary involvement of the mitral–aortic intervalvular fibrosa and the anterior mitral leaflet (subaortic structures) can occur in patients with aortic valve endocarditis. The secondary involvement of these structures occurs as a result of direct extension of the infection from the aortic valve or as a result of an infected aortic regurgitant jet striking the ventricular surfaces of the mitral–aortic intervalvular fibrosa and the anterior mitral leaflet. The abscess of mitral–aortic intervalvular fibrosa can expand to form an aneurysm. Subsequently, this mitral–aortic intervalvular fibrosa aneurysm can develop a perforation and communicate with the left atrium, resulting in the systolic regurgitation of blood from the left ventricular outflow tract into the left atrium. Secondary infection can also occur on the ventricular surface of the anterior mitral leaflet and result in the formation of an aneurysm or perforation of anterior mitral leaflet. Methods and ResultsThis study examines the utility of transesophageal echocardiography in the detection of these subaortic complications in 55 consecutive patients with aortic valve endocarditis. A total of 24 patients (44%) had involvement of subaortic structures, including four with an abscess in the mitral–aortic intervalvular fibrosa, four with mitral–aortic intervalvular fibrosa aneurysm, seven with perforation of the mitral–aortic intervalvular fibrosa with communication into the left atrium, two with an aneurysm of the anterior mitral leaflet, and seven with perforation of the anterior mitral leaflet. The transesophageal echocardiographic findings were confirmed at surgery in 20 patients and at necropsy in two. By comparison, transthoracic echocardiography visualized these lesions in five of 24 patients (21%), including none of four with mitral–aortic intervalvular fibrosa abscesses, two of four with mitral–aortic intervalvular fibrosa aneurysms, one of seven with mitral–aortic intervalvular fibrosa perforations, one of two with anterior mitral leaflet aneurysms, and one of seven anterior mitral leaflet perforations. Eccentric mitral regurgitation-type systolic jets were noted in eight additional patients by transthoracic color flow imaging, and this finding suggested the possibility of these unusual subaortic complications. If these patients are included, then transthoracic echocardiography suggested the presence of these subaortic complications in 13 of 24 patients (54%). ConclusionsThe results indicate that 1) involvement of the subaortic structures in patients with aortic valve endocarditis may be more common than previously recognized, 2) patients with aortic valve endocarditis and eccentric jets of mitral regurgitation on transthoracic echocardiography should undergo further evaluation by transesophageal echocardiography to exclude these unusual complications, 3) precise recognition of these complications is of value in the optimal medical and surgical management of these patients, and 4) these complications maybe responsible for unexplained congestive heart failure and hemodynamic deterioration in some patients with aortic valve endocarditis.

Use of amiodarone in the treatment of persistent and paroxysmal atrial fibrillation resistant to quinidine therapy

The efficacy of amiodarone was assessed in 38 patients with atrial fibrillation resistant to quinidine and an effort made to identify factors correlated with amiodarone response. The study group included 29 patients with and 9 without organic heart disease and either persistent (n = 11) or paroxysmal (n = 27) atrial fibrillation. All patients were treated with amiodarone and followed up in a research clinic. Efficacy was classified as excellent (no recurrent symptomatic atrial fibrillation) in 15 (55%) of 27 patients with paroxysmal and 5 (45%) of 11 patients with persistent atrial fibrillation. Efficacy was poor (no effect on atrial fibrillation) in 5 (19%) of 27 patients with paroxysmal and 6 (55%) of 11 patients with persistent atrial fibrillation. Efficacy was good (amelioration but not total suppression) in 7 (26%) of 27 patients with paroxysmal atrial fibrillation. Efficacy was related to echocardiographic left atrial dimension, left ventricular ejection fraction and, in patients with persistent atrial fibrillation, the duration of the arrhythmia. During the follow-up period of 15 months (range 1 to 36), overall efficacy (considering response and toxicity) was 67% in the 27 patients with paroxysmal and 45% in the 11 patients with persistent atrial fibrillation. It is concluded that amiodarone offers an additional therapeutic alternative in quinidine-resistant atrial fibrillation and that certain clinical factors are correlated with amiodarone response.

Reat-time inferior vena caval ultrasonography: normal and abnormal findings and its use in assessing right-heart function.

We studied the inferior vena cava (IVC) as an index of right-heart function in 111 patients. A two-dimensional echocardiographic sector was used to visualize the IVC, and its M-mode cursor was used to generate a time-motion record of the IVC size and pulsation. Normal subjects had a small presystolic A wave (less than 125% of the end-diastolic IVC dimension), a small systolic V wave (less than 140% of the enddiastolic IVC dimension), and a 50% inspiratory decrease in IVC dimension. The A wave was absent in patients with atrial fibrillation. When normalized for body surface area, mean end-diastolic IVC dimension correlated with mean right atrial pressure (r = 0.72, p < 0.001). An A wave > 125% of end-diastolic IVC dimension was recorded in 71% of patients with sinus rhythm and an elevated right ventricular end-diastolic pressure of 10 mm Hg or greater, but in no patient with right ventricular end-diastolic pressure of less than 10 mm Hg (p < 0.001). A V wave 140% of end-diastolic IVC dimension was recorded in 75% of patients with severe tricuspid insufficiency, but in no patient with mild or no tricuspid insufficiency (p < 0.001). The inspiratory decrease in IVC dimension correlated with radionuclide right ventricular ejection fraction (r = 0.75, p < 0.001); no respiratory variation in end-diastolic IVC dimension occurred in patients with significant right ventricular dysfunction (right ventricular ejection fraction less than 25%) or in patients with constrictive pericarditis.

Two-Dimensional echocardiographic determination of left atrial emptying volume: A noninvasive index in quantifying the degree of nonrheumatic mitral regurgitation

Several noninvasive techniques, including radionuclide angiography and Doppler echocardiography, have attempted to measure the regurgitant volume in patients with mitral regurgitation; however, none of these techniques are entirely satisfactory. Utilizing a computerized light pen method for tracing the left atrial endocardial border during systole and diastole in two orthogonal planes (apical four and two chamber views), biplane volume determinations were calculated in 12 normal subjects and 30 patients with nonrheumatic mitral regurgitation. Left atrial emptying volume determinations were performed by subtracting the left atrial end-diastolic volume from the left atrial end-systolic volume. The degree of mitral regurgitation was visually assessed as normal (0, trivial, Group I, 12 patients), mild (1+, Group II, 4 patients), moderate (2+, Group III, 8 patients), moderately severe (3+, Group IV, 12 patients) and severe (4+, Group V, 6 patients) by contrast left ventricular angiography and also quantitatively by regurgitant fraction at cardiac catheterization. All 18 patients with moderately severe (Group IV) and severe (Group V) mitral regurgitation had a left atrial emptying volume greater than 40 ml compared with none of the normal subjects and patients with mild (Group II) or moderate (Group III) mitral regurgitation. There was good correlation between left atrial emptying volume and mitral regurgitant fraction (r = 0.85, p less than 0.01). Thus, in patients with nonrheumatic mitral regurgitation, left atrial emptying volume is useful in separating mild from severe mitral regurgitation.

Two dimensional echocardiographic detection of intraatrial masses

With two dimensional echocardiography, a left atrial mass was detected in 19 patients. Of these, 10 patients with rheumatic mitral stenosis had a left atrial thrombus. The distinctive two dimensional echocardiographic features of left atrial thrombus included a mass of irregular nonmobile laminated echos within an enlarged atrial cavity, usually with a broad base of attachment to the posterior left atrial wall. Seven patients had a left atrial myxoma. Usually, the myxoma appeared as a mottled ovoid, sharply demarcated mobile mass attached to the interatrial septum. One patient had a right atrial angiosarcoma that appeared as a nonmobile mass extending from the inferior vena caval-right atrial junction into the right atrial cavity. One patient had a left atrial leiomyosarcoma producing a highly mobile mass attached to the lateral wall of the left atrium. M mode echocardiography detected six of the seven myxomas, one thrombus and neither of the other tumors. Thus, two dimensional echocardiography appears to be the technique of choice in the detection, localization and differentiation of intraatrial masses.

Two-dimensional echocardiographic recognition of left ventricular pseudoaneurysm.

Five consecutive patients with proved left ventricular pseudoaneurysm (PA) and 22 patients with true aneurysm (TA) were studied by two-dimensional echocardiography (2DE). In four of the five patients with PA, 2DE successfully displayed the PA. The unique 2DE characteristics of PA include: (1) a sharp discontinuity of the endocardial image at the site of the PA communication with the left ventricular cavity; (2) a saccular or globular contour of the PA chamber; and (3) the presence of a relatively narrow orifice in comparison with the diameter of the PA fundus.In addition, 2DE detected the presence of thrombotic material within the extraventricular chamber in three of four cases. By deriving the ratios of the end-systolic orifice to diameter measurements for the patients with PA (0.37 ± 0.07) compared with TA (1.00 ± 0.08), we found that 2DE reliably differentiated PA from TA (p <0.001).We conclude that 2DE is a useful noninvasive method for revealing left ventricular PAs and for distinguishing PA from TA. Considering the high risk of spontaneous rupture associated with pseudoaneurysms, this noninvasive capability is of paramount clinical importance.

Diastolic mitral regurgitation in patients with atrioventricular conduction abnormalities: a common finding by doppler echocardiography

M-mode and Doppler echocardiography were performed in 16 patients with first degree atrioventricular (AV) block, 1 patient with second degree (Wenckebach type) and 3 patients with third degree AV block; 20 individuals with a normal PR interval served as control subjects. The time from the onset of the P wave to the mitral valve closure by M-mode and to the end of mitral flow by Doppler echocardiography were obtained. In 20 normal subjects, the P wave to mitral valve closure interval measured 220 +/- 30 ms by M-mode and to the end of mitral flow 225 +/- 29 ms by Doppler technique (p = NS). In patients with first degree AV block, these intervals measured 242 +/- 41 and 249 +/- 36 ms, respectively (p = NS). Late diastolic (before the onset of the QRS complex) mitral regurgitation was detected by pulsed mode Doppler imaging in 9 (56%) of the 16 patients with first degree AV block but in none with a normal PR interval. In the four patients with advanced AV block, intermittent mid or late diastolic mitral regurgitation was found to depend on the position of the P wave in diastole. With early diastolic P waves, the end of mitral valve flow by Doppler technique occurred 230 to 250 ms after the onset of the P wave and was followed by mild diastolic mitral regurgitation of variable duration. With P waves falling in systole, the mitral valve remained open throughout diastole; during most of diastole, however, there was neither forward mitral flow (diastasis) nor diastolic mitral regurgitation detected by Doppler technique.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of two-dimensional and M-mode echocardiography in the evaluation of patients with infective endocarditis

M-mode and two-dimensional echocardiographic evaluation of infectious endocarditis and its complications was reviewed. In 21 consecutive patients with clinical endocarditis, 22 valves were involved (12 aortic, 5 mitral and 5 tricuspid). M-mode echocardiography detected vegetations in 10 patients (four aortic, two mitral and four tricuspid) and detected complications of endocarditis in 2 patients (one aortic root abscess and one flail aortic cusp). Two-dimensional echocardiography detected vegetations in 9 patients (four aortic, one mitral and four tricuspid) and detected complications in ten patients (five flail aortic cusps, one aortic root abscess, one sinus on Valsalva aneurysm, two flail mitral leaflets and one flail tricuspid valve). Thus, although M-mode and two-dimensional echocardiography had a similar ability to detect actual vegetations, two-dimensional echocardiography was superior to M-mode echocardiography in diagnosing complications of the destructive process.

Two dimensional echocardiographic diagnosis of aortic dissection

The usefulness of two dimensional echocardiography in establishing the diagnosis of aortic dissection was evaluated. Forty-two patients were referred for study; 15 had a dissection and 27 did not. Two dimensional echocardiography detected the intimal flap in 12 of 15 patients with a dissection, the three false negative studies were in patients with a localized dissection. There was one false positive study in the 27 patients who did not have a dissection.