Retrograde atrial kick in acute aortic regurgitation. Study of mitral and pulmonary venous flow velocities by transthoracic and transesophageal echocardiography.

BACKGROUND AND HYPOTHESIS: The purpose of this study was the comprehensive evaluation of the changes in pulmonary venous and mitral flow velocities of patients with acute and chronic severe aortic regurgitation. Transmitral flow velocities obtained with pulsed-wave Doppler echocardiography have been used to provide information on left ventricular (LV) filling and diastolic function. Pulmonary venous flow tracings are an important adjunct to LV inflow pattern in assessing LV diastolic function. METHODS: Fourteen patients with severe aortic regurgitation (8 chronic and 6 acute) and in sinus rhythm were examined by transthoracic and transesophageal pulsed Doppler echocardiography. Mitral and pulmonary flow velocities were recorded and compared. All patients had ejection fractions > 40%. RESULTS: Early mitral flow peak velocity was higher in patients with acute regurgitation (p < 0.001). The mitral A wave was absent in five patients with acute regurgitation. In contrast, a prominent reverse atrial pulmonary systolic wave AR was demonstrated in these patients. Peak diastolic velocity of the pulmonary venous flow was greater in patients with acute aortic regurgitation (0.76 +/- 0.13) than in patients with chronic aortic regurgitation (0.40 +/- 0.09) (p < 0.001). Peak systolic velocity did not differ significantly between the two groups. The systolic fraction of pulmonary venous flow in patients with acute aortic regurgitation was lower (0.43 +/- 0.05) than that of patients with chronic regurgitation (0.63 +/- 0.1) (p < 0.01). All patients with acute aortic regurgitation had an S/D ratio < 1, while those with chronic regurgitation had an S/D > 1 (p < 0.001) and an E/A < 1. CONCLUSION: Patients with severe acute aortic regurgitation showed a retrograde atrial kick (absence of transmitral A wave with prominent pulmonary AR wave). These patients had an S/D ratio < 1 (restrictive Doppler pattern). Patients with chronic aortic regurgitation exhibited a Doppler pattern of abnormal LV relaxation (E/A < 1, S/D > 1).

[Identification of intramural aortic hematoma by transesophageal echocardiography]. / Identificación del hematoma intramural aórtico por ecocardiografía transesofágica.

BACKGROUND AND AIM: The usefulness of transesophageal echocardiography in the diagnosis and assessment of patients with aortic dissection has been widely demonstrated. The aim of this study was to evaluate the role of this technique in the detection of intramural aortic hematoma and in the follow-up of these patients. METHODS: The records of 51 patients with aortic dissection by transesophageal echocardiography diagnosed between May 1990 and May 1994 were reviewed. RESULTS: The diagnosis of intramural aortic hematoma was established in 6 patients by transesophageal echocardiography (11%). This diagnosis was confirmed either anatomically (3 patients) or with an additional diagnostic technique (computed tomography or magnetic resonance imaging) and on the basis of echocardiographic follow-up changes (3 patients). CONCLUSIONS: Intramural aortic hematoma represents an infrequent variant of aortic dissection that can be detected by transesophageal echocardiography and is usually unrecognized by aortography.

[Morphological and quantitative analysis of the mechanism of balloon angioplasty. An intravascular ultrasonic study]. / Análisis morfológico y cuantitativo del mecanismo de angioplastia con balón. Estudio con ecografía intravascular.

BACKGROUND AND OBJECTIVES: Intracoronary ultrasound allows to study in vivo the morphology of the arterial wall, the presence and composition of atheroma and the associated lumen encroachment. The objective of our study was to assess the value of intravascular ultrasound to determine the dilatation mechanism after a conventional balloon angioplasty. PATIENTS AND METHODS: Sixteen patients were examined with intravascular ultrasound before and after they had undergone percutaneous transluminal coronary angioplasty. A mechanical intravascular ultrasound system was used. Two different types of imaging catheters were used in this study: a 20 MHz, 4.8 F catheter in 5 patients and a 30 MHz, 3.5 F in 11 patients. RESULTS: Quantitative and qualitative assessments were made from the angiograms and the ultrasound images. Seven out of 16 patients had a calcified plaque, in 8 patients the plaque was fibrotic and in 1 patient soft. Rupture of the plaque was the most common dilatation pattern. Post-PTCA the cross-sectional arterial area was increased from 15.3 +/- 5.2 mm2 to 17.3 +/- 6.2 mm2, the intraluminal area was increased from 2.7 +/- 2.5 mm2 to 7.3 +/- 3.4 mm2, and the plaque area was reduced from 12.3 +/- 4.8 mm2 to 9.7 +/- 3.4 mm2. The quantitative analysis showed that the "most frequent dilatation mechanism" found was the reduction of size plaque, an increase in cross-sectional arterial area was present in only 4 patients (25%). The incidence of depth rupture of the plaque was greater in patients with a calcified plaque than in those without (NS). CONCLUSIONS: 1). Intracoronary ultrasound provides a complete description of plaque composition and geometry before and after coronary balloon angioplasty; 2) several morphologic dilatation patterns were found, and plaque tearing was the most common, and 3) increase in luminal area was most frequently due to a reduction in plaque area. Nevertheless an increase in the cross-sectional arterial area was also common, but less important.

[The evaluation of the mechanism of mitral bioprosthesis malfunction by transesophageal echocardiography]. / Valoración del mecanismo de disfunción de las bioprótesis mitrales mediante ecocardiografía transesofágica.

OBJECTIVES: The aim of this study was to assess the usefulness of transesophageal echocardiography for detection of the mechanism of dysfunction in bioprosthetic valves in the mitral position. METHODS: Transthoracic and transesophageal echocardiograms were performed in 40 patients (mean age 61 +/- 12 years) with a dysfunctional bioprosthetic mitral valve. Echocardiographic results were compared to surgical findings in all except 1 patient. RESULTS: All 9 patients with stenotic degenerated bioprosthesis were diagnosed by transthoracic and transesophageal echocardiography. Mechanism of dysfunction in the remaining patients were as follows: cusp tear or rupture in 18, dehiscence in 4 and endocarditis in 6. Transthoracic and transesophageal echocardiography visualized respectively: 8 (44%) and 15 (83%; p < 0.05) with cusp tears or ruptures; 3 (75%) and 3 (75%) with dehiscence; 3 (50%) and 6 (100%; p < 0.1) with endocarditis. One patient with pannus formation and 1 of 2 bioprosthetic thrombosis were not correctly identified by either echocardiographic technique. CONCLUSIONS: Transesophageal echocardiography is suited for the assessment of mechanism of mitral regurgitation and for the diagnosis of vegetations in most of patients with bioprosthetic mitral valves. Transesophageal echocardiography adds little information to the transthoracic study in the evaluation of patients with stenotic bioprosthetic mitral valves, particularly in calcified degeneration.