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Mahbubul Alam

Publications and source records attributed to Mahbubul Alam.

7 recordsLinked to original sources
PubMed2003

Right ventricular function before and after an uncomplicated coronary artery bypass graft as assessed by pulsed wave Doppler tissue imaging of the tricuspid annulus.

BACKGROUND: Right ventricular (RV) function using myocardial velocities before and after a coronary artery bypass graft (CABG) is not known. METHODS: Using pulsed wave Doppler tissue imaging, RV function was studied in 35 patients before and after CABG. Patients were followed-up for 1 year after the CABG. Myocardial velocities at the tricuspid annulus at the RV free wall were recorded from the apical 4-chamber views. RESULTS: Both the systolic and early diastolic tricuspid annular velocities (TAV) were significantly reduced 1 month after CABG (P <.001 for both). During the follow-up period, there was no improvement in the diastolic TAV. The systolic TAV showed no improvement 3 months after CABG but recovered partially 1 year after the CABG (systolic velocities were 11.8, 8.7, 8.7 and 9.7 cm/s, the early diastolic velocities were 11.0, 8.1, 8.1 and 8.2 cm/s before and 1 month, 3 months and 1 year after the CABG, respectively). The systolic and early diastolic velocities of the interventricular septum were unchanged during the follow-up period. Unlike the right ventricle, the mitral annular systolic velocity was unchanged shortly after CABG and showed signs of improvement after 1 year (6.4, 6.9, 6.8 and 7.3 cm/s respectively before and after CABG). Patients underwent dobutamine stress echocardiography (DSE) before and 3 months after the CABG. The systolic TAV increased significantly during the DSE before CABG (11.8 vs 15.8 cm/s, P <.001). However, the increase in systolic TAV was limited during DSE 3 months after CABG (8.7 vs 9.9 cm/s, P <.05). CONCLUSION: RV function, as assessed by TAV, decreased significantly after CABG and the changes were still evident after 1 year. The response of systolic TAV during DSE was more pronounced before CABG than after CABG.

Aged↗
PubMed2003

Assessment of left ventricular function using mitral annular velocities in patients with congestive heart failure with or without the presence of significant mitral regurgitation.

Myocardial velocities in patients with congestive heart failure (CHF) were studied using pulsed wave Doppler tissue imaging. Velocities were recorded at the mitral and tricuspid annulus. Four sites at the mitral annuli were selected corresponding to the septal, lateral, inferior, and anterior walls of the left ventricle from apical 4- and 2-chamber views. A mean value from the above 4 sites was selected to describe the mitral annular velocities. Only one site of the tricuspid annulus was selected, corresponding to the right ventricular free wall. Three different annular velocities were recorded: the peak systolic, and the peak early and late diastolic velocities. A total of 96 patients were compared with 12 age-matched healthy participants. Patients with CHF had significantly decreased mitral and tricuspid systolic velocities compared with healthy participants (4.9 vs 9.3 cm/s, P <.001, for the mitral annulus and 10.4 vs 14.6 cm/s, P <.001, for the tricuspid annulus). The early diastolic velocity was also reduced in patients compared with healthy participants (5.9 vs 10.9 cm/s, P <.001, for the mitral annulus and 8.6 vs 12.9 cm/s, P <.001, for the tricuspid annulus). Patients with CHF had a severely depressed left ventricular ejection fraction (EF) (27%). The correlation the between systolic mitral annular velocity and EF was relatively good (r = 0.59 and P <.001). The patients with CHF were divided into 2 subgroups depending on the presence or absence of significant mitral regurgitation. There was a correlation between EF and the systolic mitral annular velocity both in patients with (r = 0.61, P <.001) and without (r = 0.59, P <.001) significant mitral regurgitation. In conclusion, compared with healthy participants, the mitral and tricuspid annular velocities are significantly decreased in patients with CHF. The correlation between EF and the systolic mitral annular velocity is relatively good irrespective of the presence or absence of significant mitral regurgitation. Measurements of annular velocities constitute a simple and useful method for evaluating patients with CHF.

Aged↗
PubMed2002

Acute effects of smoking on diastolic function in healthy participants: studies by conventional doppler echocardiography and doppler tissue imaging.

The acute effects of smoking on left ventricular (LV) function were studied in 36 healthy participants (mean age 38 +/- 10 years). The studies were made before and immediately and 30 minutes after smoking a cigarette. From apical 4- and 2-chamber views, the mitral annular velocities, determined by pulsed wave Doppler tissue imaging, were measured at 4 LV sites corresponding to the septum and the anterior, lateral, and inferior walls. A mean value from the 4 sites was used to assess LV function. The peak systolic, early diastolic, late diastolic, and the ratio of early to late diastolic velocities were recorded. In addition, other conventional Doppler echocardiographic diastolic parameters were also determined. Heart rate was increased immediately after smoking (from 67 +/- 8 to 74 +/- 10 bpm, P <.001). There was no change in systolic mitral annular velocity. Diastolic LV function was changed significantly immediately after smoking. The transmitral A wave increased (0.55 +/- 0.1 vs 0.7 +/- 0.1 m/s, P <.001), the transmitral E/A ratio decreased (1.5 +/- 0.6 vs 1.1 +/- 0.3, P <.001), and the transmitral E-wave deceleration time increased (186 +/- 42 vs 211 +/- 44 ms, P <.05). The diastolic myocardial velocity at the mitral annulus also changed significantly: the early diastolic velocity decreased (16 +/- 3 vs 15 +/- 3 cm/s, P <.001), the late diastolic velocity increased (10.9 +/- 2.2 vs 12 +/- 2.4 cm/s, P <.001), and the ratio of early to late diastolic annular velocities decreased (1.5 +/- 0.5 vs 1.2 +/- 0.4, P <.001). The changes in the transmitral flow velocities remained unaltered even 30 minutes afterward, although the heart rate returned to normal. The results were similar in both smokers and nonsmokers. Acute smoking of a cigarette influences LV diastolic function in healthy participants. The mechanism behind this effect cannot be explained only by changes in the heart rate or loading conditions. The mechanism is probably more complex.

Adult↗
PubMed1999

Left Ventricular Regional Diastolic Dysfunction in Patients with First Myocardial Infarction Determined by Diastolic Motion of the Atrioventricular Plane.

Motion of the left ventricular [left ventricle (LV)] atrioventricular (AV) plane has been used to assess systolic LV function. The method has not been used properly to assess diastolic function, especially after a first myocardial infarction (MI). The diastolic function was assessed in 47 previously healthy patients with a first MI assessed by echocardiographic diastolic motion of the LV AV plane. The motion of the AV plane was recorded at four different LV sites, that is, at the septal, anterior, lateral, and inferior walls. Two distinct phases of motion were noticed during diastole at all the sites: one at the early diastole caused by rapid filling of the LV and the other at late diastole during the atrial contraction. The contribution of left atrial contraction to LV filling at different LV sites was calculated by relating the magnitude of the motion caused by atrial contraction to the total diastolic AV plane motion at the respective sites. These left atrial contributions were regarded as the regional diastolic function of the respective LV sites. The global LV diastolic function was determined from the left atrial contribution to total AV plane motion from the above four sites. Patients with anterior MI had a significantly lower ejection fraction than those with inferior MI (41% and 49%, respectively; P < 0.01). Compared with age-matched healthy subjects, the regional atrial contribution to diastolic filling was significantly higher at the anterior wall in anterior MI (38% and 52%, respectively; P < 0.001) and at the inferior wall in inferior MI (43% and 53%, respectively; P < 0.01). The atrial contribution to global LV filling was increased in anterior MI (48% compared with 42% in healthy subjects; P < 0.05) but not in inferior MI. These findings suggest that the diastolic AV plane displacement (AVPD) may be used to assess both the regional and the global diastolic function in patients following an MI.

Journal Article↗
PubMed1999

Effects of Low-Dose Dobutamine on Displacement of the Atrioventricular Plane and Assessment of Myocardial Viability in Patients with Acute Myocardial Infarction Treated with Thrombolysis.

Previous echocardiographic studies have highlighted the usefulness of atrioventricular (AV) plane displacement (the mitral annular motion) in assessing left ventricular function at rest. However, the effects of low-dose dobutamine on AV plane displacement in thrombolyzed patients with acute myocardial infarction (AMI) are unknown. Thirty-four patients with AMI treated with a thrombolytic agent and having rest wall motion abnormalities at the infarct site were studied with rest and low-dose dobutamine echocardiography before discharge. Thirty-one patients were followed up 18 months later with rest echocardiography. The systolic descent of the AV plane toward the apex at four different left ventricular sites (i.e., at the septal, anterior, lateral, and inferior walls) was recorded to assess left ventricular function. Compared with age-matched healthy subjects, the AV plane displacement was significantly reduced, especially at the infarct sites, in AMI patients at rest. During low-dose dobutamine, the AV plane displacement was increased at infarct sites (P < 0.001) in patients with signs of viability. A cutoff point of an increase in AV plane displacement of >/= 2 mm at the infarct sites during low-dose dobutamine stress had a sensitivity of 89% and a specificity of 87% in assessing myocardial viability. Using the same cutoff point of a spontaneous increase in the AV plane displacement of >/= 2 mm during the follow-up rest echocardiography, 87% of the patients with initial signs of viability and only 25% without signs of viability showed a spontaneous late recovery of initially stunned myocardium. Thus, the study shows that changes in the amplitude of the AV plane displacement during low-dose dobutamine stress echocardiography can easily be used to detect myocardial viability at an early stage with late potential spontaneous recovery.

Journal Article↗