Clinical Significance of Heart Chronotropic Incompetence in Patients With Coronary Heart Disease

Yingjun Feng; Handong Yang; Xinwen Min; Xin Chen; Dongfeng Li; Hao Xu

摘要：Objectives To investigate the relationship between the chronotropic incompetence and angiographic severity of coro-nary artery disease, and the clinical value of inappropriate chronotropic responses in exercise. Methods Coronary an-giography was performed in 130 patients suspected or diagnosed as coronary heart disease (CHD), and angiographic se-verity of coronary artery disease was quantitated by Duke score and Gensini score. The patients were divided into 4groups: non-CHD group (39 cases), CHD group with only one coronary artery involved (CHD1, 30 cases), CHD group with two coronary arteries involved (CHD2, 31 cases) and CHD group with three coronary arteries involved (CHD3 group, 30 cases). A month before coronary angiography, symptom-limited bicycle ergometor exercise had been accomplished, the chronotropic response had been measured and expressed as ratio of heart rate reserve (HRR)and the maximal age-predicted heart rate achieved (rHR). Results Analysis of variance showed that rHR and HRR were much significantly lower (all P < 0. 01) in CHD2 group (rHR 0. 793± 0. 078, HRR 0. 626± 0. 110) and CHD3group (rHR 0. 775±0. 065, HRR 0. 586±0. 125) than that in non-eHD group (rHR 0. 888±0. 062, HRR 0. 798±0. 105)and CHD1 group(rHR 0. 857±0. 084, HRR 0. 735±0.146). rHR was similar both between non-CHD group and CHDI group(P >0.05)and between CHD2 group and CHD3 group(P>0.05). HRR has no difference between CHD2 group and CHD3 group (P >0.05), but was significandy different between non-CHD group and CHD1 group (P <0. 05). There was a significantly negative correlation between rHR, HRR and Duke score(r = -0. 554, -0. 578, respectively, all P <0. 01), Gensini score (r = -0. 453, -0. 467 ,respectively, all P <0. 01). CHD propor-tion reached 75% in patients who had positive rHR (or HRR) and non-ST depression. Diagnostic value [sensitivity 0. 868 (P < 0. 01), 0. 846 (P < 0. 01), specificity 0. 462, 0. 462, accuracy 0. 746 (P < 0. 05), 0. 731, positive predic-tive value 0. 790, 0. 786, negative predictive value 0. 600, 0. 563, respectively] ofrHR <85% or HRR <72% which were used as annexed positive. Standard in the patients without ST depression in symptom-limited exercise treadmill tests was a little higher than that of traditional ST standard (sensitivity 0. 637, specificity 0. 641, accuracy 0. 638, posi-tive predictive value 0. 806, negative predictive value 0. 431). Conclusions There is negative correlation between car-diac chronotropic and angiographic severity of coronary artery disease and the chronotropic incompetence may predict angiographic severity of coronary disease. In patients with positive rHR (or HRR) and non-ST depression, CHD pro-portion is very high. rHR <85% or HRR <72% may be used as annexed positive standard in symptom-limited exer-cise treadmill tests.