Pulmonary echocardiography

Marrouche Np et al, Phased-array intracardiac echocardiography monitoring during pulmonary vein isolation in patients with atrial fibrillation impact on outcome and complications. Circulation 2003 107(21 ) 2710-271 6. 

The above study was based on information derived from the General Practice Research Database in the UK. Subjects who had been given at least one prescription for dexfenfluramine, fenfluramine, or phentermine after 1 January 1988, and who were 70 years or younger at the time of their first prescription were included. Subjects were considered to have a new cardiac abnormality if they had no history, on the basis of clinical records, of cardiac valvular abnormahties and if there was evidence of a new valvular disorder on the basis of echocardiography or chnical examination after exposure to appetite suppressants. All the data had been recorded before the pubhcation of recent reports of an association between appetite suppressants and cardiac valve disorders (25,27,30-32) or primary pulmonary hjq)ertension (14). Hence, it was possible to exclude the possibihty that enhanced awareness of possible serious adverse effects of appetite suppressants had led to closer surveillance of patients who were taking these drugs. Nevertheless, the study did not provide information on the frequency of idiopathic cardiac valve disorders that are asymptomatic or otherwise not chnicaUy diagnosed. 

Pulmonary artery pressure and cardiac valvular status were determined in a series of 156 mostly asymptomatic patients taking fenfluramine and phentermine (59). The anorexigen was withdrawn when abnormalities were noted. Pulmonary artery pressure was estimated and valvular examination was performed using Doppler echocardiography. There was borderline or mildly elevated pulmonary artery pressure in 21 patients and 31 patients had notable valvular abnormalities. It has therefore been established that asymptomatic patients may have significant echocardiographic abnormalities, representing early lesions. 

Two 19-year-old-girls developed pulmonary edema after taking massive overdoses of verapamil (6000 mg and 7200 mg). In each case a chest X-ray showed diffuse bilateral patchy infiltration. Left ventricular size and function was normal on transthoracic echocardiography. They were both treated successfully with mechanical ventilatory support. 

Verma A, Marrouche NF, Natale A. Pulmonary vein antrum isolation intracardiac echocardiography-guided technique. / Cardiovasc Electrophysiol 2004 15 1335-40. 

Verma A, Kilicaslan F, Adams JR, et al. Extensive ablation during pulmonary vein antrum isolation has no adverse impact on left atrial function an echocardiography and cine computed tomography analysis. J Cardiovasc Electrophysiol 2006 17 741-6. 

Echocardiography is a noninvasive tool that can provide assessment of possible causes, shunts, left atrial hypertension, left ventricular dysfunction, valvular heart disease, and consequences of pulmonary hypertension. Measurements of RV systolic and diastolic pressures, and associated findings of paradoxical septal motion, diminished IVC collapse, RVH, right atrial (RA) or right ventricular (RV) enlargement, pericardial effusion, and decreased RV ejection time should all be included in the assessment of these patients. The measurement of PA pressures can be done with relative precision and varying degrees of correlation with invasive measures. 

Thus, echocardiography is recommended as a screening tool, but not as the definitive diagnostic tool in patients suspected of having pulmonary hypertension. For a particular patient, following the initial correlation of the echo estimate of PA pressure with direct catheterization measurement will allow subsequent patient specific correlations. Tricuspid annular plane systolic excursion (TAPSE) has been shown to correlate strongly with RV ejection fraction as assessed by radionuclide angiography (34). It has been used in both two- and three-dimensional evaluations, and as a means of serial follow-up studies of... 

Mahapatra S, Nishimura RA, Oh JK, et al. The prognostic value of pulmonary vascular capacitance determined by Doppler echocardiography in patients with pulmonary arterial hypertension. J Am Soc Echocardiogr 2006 19 1045-50. 

Pignone A, Mori F, Pieri F, et al. Exercise Doppler echocardiography identifies preclinic asymptomatic pulmonary hypertension in systemic sclerosis. Ann N Y Acad Sci 2007 1108 291-304. 

Kim, Y.Y., et al.. Left atrial appendage filling defects identified by multidetector computed tomography in patients undergoing radiofrequency pulmonary vein antral isolation a comparison with transesophageal echocardiography. Am Heart J, 2007. 154(6) p. 1199-205. 

In the early 1980s, clinical echocardiography was performed with a sector scanner, a stand-alone Doppler unit capable of a pulsed and continuous-wave mode operation, a spectral analyser with high temporal resolution and an in-house black box which allowed EKG display along with the spectra (Gramiak and Holen 1984). Due to the fact that small gas bubbles dissolve rapidly in blood, the next aim was the production of agents small enough to traverse the pulmonary capillary bed. 

Barzilai B, Waggoner AD, Spessert C, Picus D, Gooden-berger (1991) Two-dimensional contrast echocardiography in the detection and follow-up of congenital pulmonary arteriovenous malformations. Am J Cardiol 68 1507-1510... 

Gossage JR (2003) The role of echocardiography in screening for pulmonary arteriovenous malformations. Chest 123 320-322... 

Lee WL, Graham AF, Pugash RA, Hutchinson SJ, Grande P, Hyland RH, Faughnan ME (2003) Contrast echocardiography remains positive after treatment of pulmonary arteriovenous malformations. Chest 123 351-358... 

Echo has been used to assess aU levels of mechanical dyssynchrony dys-synchrony between the atrium and the ventricle, interventricular dyssynchrony, and intraventricular dyssynchrony. Echo Doppler imaging at the level of the mitral valve inflow shows the effects of a long AV interval (fused E and A waves with diastolic mitral regurgitation), short AV interval (truncation of A wave with loss of atrial kick), and optimal AV interval (aortic systolic flow starts at the end of A wave) (5,31). This is illustrated in Fig. 11.4. Pulsed-wave Doppler echocardiography has been used to evaluate interventricular dyssynchrony that is defined as the time difference between right and left ventricular pre-ejection intervals. This is usually measured from the onset of the QRS complex on the EKG (that correlates with the end of diastole) to the onset of the aortic and pulmonary ejection. Delayed aortic ejection time (>40-50ms) has been used as a marker of interventricular dyssynchrony that improves with CRT (32-34). 

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