Background:

The intervention timing in atrial septal defect (ASD) or pulmonary valvular stenosis (PVS) is more

dependent on symptoms than right ventricular (RV) damage in clinical practice. RV long-axis function is sensitive

in revealing RV myocardial dysfunction. We evaluate the impact of different chronic loading conditions on RV

long-axis function and its relationship to patients' symptoms in ASD or PVS.

Methods:

Transthoracic echocardiography was performed in normals (n=39) and patients with isolated secundumASD(

n=45) or PVS (n=38). RVvolume- and pressure-overloadingwere de

finedas the ratioofRV/leftventricular

end-diastolic dimension

≥0.5 and RV systolic pressure ≥40mmHg, respectively. RV long-axis

dysfunction was de

fined as M-mode tricuspid annular plane systolic excursion (TAPSE) b1.6 cm. New York

Heart Association (NYHA) functional class and other symptoms (decreased exercise tolerance, palpitation and

chest pain) were recorded.

Results:

Thirty-nine (32.0%) had normal loading (Group 1; 39 normals); 24 (19.6%) had isolated volumeoverloading

(Group 2; all ASDs); 21 (17.2%) had isolated pressure-overloading (Group 3; 21 PVSs) and 38

(31.1%) had both overloading conditions (Group 4; 21 ASDs and 17 PVSs). RV long-axis dysfunction in abnormal

loading groups were zero (0%, Group 2), 21 (100%, Group 3) and 22 (57.8%, Group 4) (

χ2=45.9, pb0.001).

Group 3 were more symptomatic (NYHA functional class 2.5±0.6 versus 1.6±0.5, p

b0.05) and had lower

TAPSE (1.6±0.4 versus 3.0±0.7 cm, p

b0.05) than Group 2. RV long-axis dysfunction was the strongest predictor

of the presence of symptoms (odds ratio=9.298, p

b0.001).

Conclusion:

Chronic volume-overloading accentuates while pressure-overloading attenuates RV long-axis excursion

and its impairment was associated with the presence of symptoms.