title: Usefulness of systolic time intervals in the identification of abnormal ventriculo-arterial coupling in stable heart failure patients.
abstract: BACKGROUND
  The ratio of effective arterial elastance (Ea) to ventricular end-systolic elastance (Ees) indicates the status of ventriculo-arterial coupling.
  
  
  OBJECTIVE
  We investigated if systolic time intervals (pre-ejection period, PEP; ejection time, ET; and their ratio, PEP/ET) can be used to identify heart failure patients with abnormal ventriculo-arterial coupling.
  
  
  METHODS
  Age and sex-matched study subjects included 54 apparently healthy subjects with normal left ventricular (LV) function, and stable patients with LV diastolic (n=54) and systolic dysfunction (n=54). Ees and Ea were estimated non-invasively by echocardiography, and abnormal ventriculo-arterial coupling was defined as Ea/Ees>1.2. PEP, ET, and PEP/ET were measured automatically using electrocardiography, phonocardiography, and brachial pulse volume recording.
  
  
  RESULTS
  Ea/Ees>1.2 was present in 48.1% of subjects with systolic dysfunction. The PEP/ET was significantly associated with most parameters of LV structure and function, and Ea/Ees (r=0.67, p<0.001). Using PEP/ET> or =0.423 as cut point, the sensitivity and specificity to identify patients with Ea/Ees>1.2 were 85.7% and 84.3%, respectively for the whole population, and 84.6% and 78.6%, for patients with systolic dysfunction.
  
  
  CONCLUSIONS
  Abnormal ventriculo-arterial coupling was present in almost half of stable patients with systolic dysfunction. PEP/ET was useful in identifying such patients.
authors.affiliation: Department of Research and Education, Taiwan.
authors.forename: Hao-Min
authors.initials: HM
authors.lastname: Cheng
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Yu
authors.forename: Shih-Hsien
authors.initials: SH
authors.lastname: Sung
authors.forename: Kang-Ling
authors.initials: KL
authors.lastname: Wang
authors.forename: Shao-Yuan
authors.initials: SY
authors.lastname: Chuang
authors.forename: Chen-Huan
authors.initials: CH
authors.lastname: Chen
mesh_terms: D000368:Aged; D001794:Blood Pressure; D016022:Case-Control Studies; D003331:Coronary Vessels / Q000503:physiopathology*; D005260:Female; D054143:Heart Failure, Systolic / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results; D013318:Stroke Volume; D013599:Systole; D013997:Time Factors; D014463:Ultrasonography; D016277:Ventricular Function, Left