Effect of age, heart rate and tricuspid regurgitation on the Doppler echocardiographic evaluation of right ventricular diastolic function

The effect of age on right ventricular diastolic function in healthy subjects undergoing treadmill exercise test

OBJECTIVE

There is an increasing interest for the value of right ventricle (RV) in predicting exercise tolerance and prognosis in cardiovascular disease. However, there is relatively few data evaluating the effect of age on RV diastolic filling velocities during rest or exercise in healthy subjects.

METHODS

A total of 54 healthy subjects were enrolled in this study. Patients were divided into 2 groups according to their age: Group 1 (≤45-years-old) and Group 2 (>45-years-old). A treadmill exercise test was performed using modified Bruce protocol. Conventional pulsed-wave Doppler and tissue Doppler velocities were obtained both at rest and immediately after the end of exercise, respectively.

RESULTS

In the overall analysis, tricuspid flow Doppler analysis showed a significant increase in A-wave velocity, less marked rise in E-wave velocity, decreased E/A ratio and decreased E-wave deceleration time (EDT) with exercise. Tissue Doppler analysis revealed increased Aa velocity, decreased in Ea/Aa ratio and IVRT. No significant change was observed in Ea velocity and E/Ea ratio with exercise. Although diastolic velocities changed significantly with exercise, systolic velocities did not. Cardiac response to exercise differed slightly in the older subjects compared to younger ones. The older subjects were more likely to have a reduced mean rate of RV filling for the second half of diastole from baseline to peak exercise.

CONCLUSION

To distinguish normal physiological changes due to aging from those of pathologic conditions may provide benefits while evaluating patients with known or suspected cardiovascular disease.

Cardiac status after childhood growth hormone treatment of Turner syndrome

CONTEXT

In Turner syndrome (TS), GH treatment is well established. Data on cardiac status after discontinuation of treatment are scarce. This study aimed to assess biventricular size and function in TS at least 6 months after discontinuation of GH treatment.

METHODS

TS patients and healthy women prospectively underwent cardiac magnetic resonance imaging. Ventricular two-dimensional tomographic cine data were acquired to obtain biventricular volume, mass, and ejection fraction. Atrioventricular valve flow measurements were performed using a two-dimensional flow-sensitized sequence. Flow velocity curves were calculated and indices of biventricular diastolic filling were derived.

RESULTS

Thirty-one patients [mean (sd) age 20 (2) yr, body surface area 1.75 (0.15) m(2), 5 (2) yr after GH discontinuation] and 23 normal control women [age 21 (2) yr, body surface area 1.80 (0.13) m(2)] were included. Compared with controls, patients had smaller mean end-diastolic volumes [right ventricle (RV), 84 (11) ml/m(2) vs. 79 (10), P = 0.02; left ventricle (LV), 81 (10) vs. 72 (9), P < 0.001], end-systolic volumes [RV 38 (7) ml/m(2) vs. 36 (6), P = 0.04; LV 34 (5) vs. 29 (4), P < 0.001], and stroke volumes [RV 46 (6) ml/m(2) vs. 43 (6), P = 0.03; LV, 47 (7) vs. 44 (4), P = 0.02]. Patients had a higher mean heart rate [79 (13) beats/min vs. 71 (10), P < 0.05]. Biventricular ejection fraction, mass, cardiac output, and diastolic filling pattern were comparable.

CONCLUSION

After discontinuation of GH treatment TS patients showed no myocardial hypertrophy and well-preserved biventricular function. Ventricular volumes were smaller in Turner patients, compared with controls, whereas mean heart rate was higher. These last observations may be part of the natural development in TS and not linked to GH treatment, which at this point we consider safe.

Reversal E/A Value at End-Inspiration Might Be More Sensitive and Accurate for Diagnosing Abnormal Left Ventricular Diastolic Function

BACKGROUND

It is well known that left ventricular (LV) filling decreases on inspiration and increases on expiration; however, respiratory effects on diastolic function have not been fully investigated.

AIM

This study attempted to provide further information on the precise diagnosis of LV diastolic dysfunction when taking respiration into account.

METHODS

Fifty-one patients with systemic hypertension and impaired LV diastolic function and 33 normal subjects were recruited. Respiratory transmitral Doppler flow parameters and the early-to-late diastolic tissue velocity ratio of the mitral annulus (e/a ratio) of the septal wall were recorded. The validity of the reversal ratio of early-to-late peak flow velocity (E/A ratio) on inspiration and on expiration for diagnosis of diastolic dysfunction was compared.

RESULTS

The E velocity was much higher and its deceleration time was much shorter on expiration compared to that on inspiration, while the A velocity demonstrated no regular respiratory variations both in normal subjects and patients. Ten of the patients displayed a phenomenon characterized with an E/A ratio < 1 on inspiration and > 1 on expiration, eight of whom revealed abnormal LV filling by Tissue Doppler imaging.

CONCLUSION

Respiratory effects on transmitral Doppler flow parameters raise the necessity of adjustment of the existing standard for precise diagnosis of diastolic dysfunction, while the characteristic phenomenon reported here indicates that reversal E/A value on end-inspiration is a more sensitive and accurate indicator of abnormal LV diastolic function.

Diastolic Function in Repaired Tetralogy of Fallot at Rest and during Stress: Assessment with MR Imaging

PURPOSE

To prospectively assess, with magnetic resonance (MR) imaging, right ventricular (RV) diastolic function after repair of tetralogy of Fallot (TOF) at rest and during pharmacologic stress and to study relationship between main pulmonary artery end-diastolic forward flow (EDFF) (indicative of restrictive RV physiology) and clinical status.

MATERIALS AND METHODS

Institutional medical ethics committee approval and patient or parent informed consent were obtained. Patients with TOF corrected through the transatrial-transpulmonary approach underwent MR imaging at rest and during dobutamine stress and maximal exercise testing. Two-dimensional (2D) cine volumetric data were acquired. Flow measurements were performed with a standard 2D flow-sensitized sequence. MR imaging flow curves for tricuspid and pulmonary valves were combined into RV time-volume change curves, from which indexes of RV filling were derived. Patient results were compared with published data in control subjects. Student t tests, Mann-Whitney U tests, analysis of covariance, and paired and one-sample t tests were used.

RESULTS

Thirty-six patients (mean age at repair, 0.9 year +/- 0.5 [standard deviation]; median age at study inclusion, 17 years [range, 7-23 years]; 26 male and 10 female patients) were included. Abnormalities in RV filling included impaired relaxation (prolonged deceleration time, P = .002; smaller early filling fraction, P = .02) in the entire group compared with published data in healthy control subjects and signs of restriction to RV filling (smaller atrial filling fraction and higher early filling/atrial filling peak ratio, P < .05 for both) in patients with EDFF (n = 24) compared with patients without EDFF (n = 12). Stress response was abnormal in patients with EDFF, who developed impaired RV relaxation not appreciated at rest. Patients with EDFF had more severe pulmonary regurgitation (P < .05) and poorer exercise performance (P < .001).

CONCLUSION

In patients with TOF corrected with currently widely accepted surgical strategies, pulmonary artery EDFF relates to worse clinical state at mid- to long-term follow-up. Dobutamine stress imaging may unmask abnormalities in RV diastolic filling not appreciated with rest imaging alone.

Relation of tricuspid inflow E-wave peak velocity to severity of tricuspid regurgitation

E-wave velocity in mitral flow has previously been shown to discriminate between severe and nonsevere mitral regurgitation. In this study, we sought to explore this association in the tricuspid position. The peak velocity of the tricuspid inflow E wave was measured in 118 patients (mean age 62 +/- 16.6 years; 48% women). Patients with tricuspid stenosis, transvenous pacemakers, and tricuspid prostheses were excluded. E-wave measurements were taken during shallow breathing. Tricuspid regurgitation (TR) was quantified as none or mild (group 1), moderate (group 2), or severe (group 3), according to American Society of Echocardiography guidelines. Forty-three patients had mild TR, 43 had moderate TR, and 33 had severe TR. Peak E-wave velocity was 48.6 +/- 13.8, 48.6 +/- 11.7, and 78.3 +/- 26.1 cm/s in groups 1, 2, and 3, respectively (p > 0.0001). Mean E-wave velocity was similar in groups 1 and 2 but greater in group 3 (p < 0.0001). A peak E-wave velocity of > or = 65 cm/s had a sensitivity of 73% and specificity of 88% for the detection of severe TR. In conclusion, increased peak tricuspid E-wave velocity is associated with severe TR and thus can be used as a simple measure of TR grade.

Intraoperative assessment of diastolic function: utility of echocardiography

PURPOSE OF REVIEW

This review discusses the current and future applications of different echocardiographic modalities in evaluating diastolic function intraoperatively.

RECENT FINDINGS

Normal diastolic function is required for optimal cardiac performance. There is sufficient evidence to support the significant prevalence of preoperative diastolic dysfunction and its incidence following cardiac surgery, however controversy still exists regarding the impact of diastolic dysfunction on adverse outcomes. Echocardiography provides a relatively safe, practical and noninvasive means to evaluate perioperative diastolic function, however conventional measures may be limited by the impact of changes in heart rate, rhythm and loading conditions. Newer echocardiographic modalities are reportedly less sensitive to acute changes in loading conditions, and may therefore complement the use of conventional echocardiographic techniques in the perioperative period.

SUMMARY

The availability of effective technology for diagnosing the presence and progression of perioperative diastolic function should assist in the identification of high-risk cardiac surgical patients who may benefit from appropriate triaging and therapeutic intervention.