Evaluation Of Right Ventricular Dysfunction In Patients With Obstructive Sleep Apnea Hypopnea Syndrome By Speckle Tracking Imaging

Using the speckle tracking imaging (STI) to evaluate the rihgt ventriculardysfunction of patients with Obstructive Sleep Apnea Hypopnea Syndrome inthe absence of pulmonary and cardiac comorbidityand and to correlate theOSAHS severity to RV dysfunction.Methods30healthy individuals and90OSAHS patients were included in this study.According to the apnea hypopnea index (AHI), OSAHS subjects were dividedinto mild, moderate and severe，30cases in each group.Right ventricularanterior wall thickness(RVAM), right ventricular end-diastolic diameter (RVDD)and tricuspid annulus plane systolic excursion (TAPSE) are measured byconventional ultrasonic;then right ventricular ejection fraction (RVEF), constantvolume (IVA), systolic acceleration isovolumetric relaxation time (IVRT), anddeceleration time (DTm) are measured by Pulsed tissue doppler ultrasound,atlast using speckle tracking imaging technology to measure the myocardialstrain and strain rate of right ventricular free wall between groups (systolicpeak strain S, systolic peak strain rate SR, early diastolic peak strain rate SRe,and late diastolic peak strain rate SRa) by Philips IE33color Dopplerultrasonic diagnostic apparatus. Results1. Clinical general characteristicsThere was no significant difference about the age, body mass index,systolic and diastolic blood pressure between the mild, moderate,severeOSAHS group and the control (P＞0.05). There were statistically significantbewteen each groups about the AHI (P＜0.05).2. Conventional and PW-TDI ultrasonic parameters(1) The index of the right ventricular structure:RVAM increased, but therewas no difference between the mild OSAHS and control group (P＞0.05).Although RVDD changed between all the groups, there were no statisticallysignificant difference (P＞0.05).(2) The index of the right ventricular systolic function：TAPSE、IVAdecreased，there were statistically difference in moderate and severe OSAHSgroups compared with the control group (P＜0.05）,but there was nostatistically significant difference bewteen the two groups(P＞0.05). Therewere difference in severe and mild OSAHS group. Although RVEF changedbetween all the groups, there were no statistically significant difference (P＞0.05).(3) The index of the right ventricular diastolic function: E/A decreased andDTm increased, there were difference in severe OSAHS group compared withcontrol group(P＜0.05), E/Em increased, there were statistically differencebetween the moderate,severe OSAHS groups and the mild OSAHS group andthe control group (P＜0.05),but there was no statistically significant differencebewteen the two groups(P＞0.05).Although IVRT changed between all thegroups, but there were no statistically significant difference (P＞0.05).3. STI parameters(1) Comparing the myocardial strain and strain rate parameter of the rightventricular free wall’s basal segment between the OSAHS groups and the control groupWith increasing severity of the disease, Moderate and severe OSAHSgroup’s the peak systolic strain SR and the strain rate SRs lower than themild OSAHS group and the control group,there was no statistically differencein moderate and severe OSAHS groups about SR(P＞0.05),but severeOSAHS group’s SRs was lower than the moderate’s,and there was statisticallydifference (P＜0.05). Right ventricular peak early diastolic strain rate SRedecreased from moderate OSAHS group,and the peak late diastolic strain rateSRa increased,although the difference of the SRa wasn’t obviously, there wasstatistically difference about SRe/SRa between the moderate and severeOSAHS group (P <0.05), and severe OSAHS group significantly.(2) Comparing the myocardial strain and strain rate parameter of the rightventricular free wall’s middle segment between the OSAHS groups and thecontrol groupWith increasing severity of the disease, moderate and severe OSAHSgroup’s the peak systolic strain SR and the strain rate SRs lower than themild OSAHS group and the control group,there was no statistically differencein moderate and severe OSAHS groups about SR(P＞0.05),but severeOSAHS group’s SRs was lower than the moderate’s,and there was Rightventricular peak early diastolic strain rate SRe and SRe/SRa decreased frommoderate OSAHS group,there was statistically difference between themoderate and severe group (P＜0.05),and there was no statistically differencebetween the moderate and the control group about SRe(P＞0.05),but therewas statistically difference about the SRe/SRa between the two groups(P＜0.05),and the peak late diastolic strain rate SRa, increased, there wasstatistically difference especially the severe OSAHS group(P＜0.05).AlthoughSRa incresed,there was only statistically difference between the severeOSAHS group and the control group(P＜0.05).(3) Comparing the myocardial strain and strain rate parameter of the rightventricular free wall’s apical segment between the OSAHS groups and the control group: With increasing severity of the disease, right ventricular peaksystolic strain SR, strain rate SRs and peak early diastolic strain rate SRedecreased from mild OSAHS group, and there was statistically significantdifference compared with the control group(P＜0.05). Right ventricular peaklate diastolic strain rate SRa increased,there was no significant differencebetween the mild OSAHS group and the control group(P＞0.05),but there wassignificant difference about the SRe/SRa(P＜0.05).4. Compariing the correlation between the AHI and theindicators of right ventricular systolic and diastolic functionThere was no correlation bewteen AHI and the E/A(r=0.463, P=0.082),speckle tracking parameters has better correlation compared with conventionalechocardiographic parameters.Conclusions1. Before the advent of pulmonary hypertension and other combinedrelevant dieseases, the right ventricular regional function has changed inOSAHS patients.2. With increasing severity of the disease, the impaired degree of rightventricular systolic and diastolic function tends to aggravate, and only mildOSAHS group apical segment myocardial damage is obvious than othergroups’ each segment.3.Speckle tracking imaging technology is a early,non-invasive andsensitive method to evaluate the right ventricular dysfunction of OSAHSpatients, and provides a new quantitative evaluation methods for early clinicaldiagnosis.