The aim of this study was to assess the incidence of perioperative myocardial damage detected by serial measurements of troponin I after hip surgery and its association with late cardiovascular outcome.
Troponin I was measured during the first three postoperative days in 88 consecutive patients undergoing hip surgery. Values above the 99th percentile (0.08 ng mL−1) were considered positive. Major cardiac events (cardiac death, myocardial infarction and cardiac failure) were recorded during hospital stay and 1 yr after surgery.
Eleven patients (12.5%) exhibited elevated troponin I levels during hospital stay. Nine of them remained asymptomatic. During follow-up, 45% of them (5/11) suffered from a major cardiac event vs. 4% (3/76) for patients with normal postoperative troponin I levels (P = 0.0006). All-cause mortality rate was 36% (4/11) at 1 yr vs. 7% (5/71, P = 0.0131). Using multivariate Cox regression analysis adjusted for baseline data, independent factors associated with the occurrence of a cardiac event were troponin I elevation (OR=17.4 - CI 95% 3.7-82) and age (OR=1.1 yr−1 - CI 95% 1.01-1.21). Independent factors for all-cause mortality were troponin I elevation (OR=41.4 - CI 95% 5.4-320.4), and age (OR=1.3 yr−1 - CI 95% 1.1-1.4).
Troponin I release is common after hip surgery and is associated with a 10-fold increased incidence of long-term major cardiac events as compared to patients with normal troponin I levels (45% vs. 4%).
*Hôpital d'Instruction des Armées Percy, Service d'Anesthésie-Réanimation, Clamart Cedex, France
†Hôpital d'Instruction des Armées Percy, Service de Biochimie, Clamart Cedex, France
¶Hôpital d'Instruction des Armées Percy, Service de Cardiologie, Clamart Cedex, France
‡Hôpital d'Instruction des Armées Percy, Service de Chirurgie Orthopédique, Clamart Cedex, France
§Bicětre University Hospital, Département d'Anesthésie-Réanimation, Le Kremlin Bicětre Cedex, France
Correspondence to: Sylvain Ausset, Service d'Anesthésie-Réanimation, Hôpital d'Instruction des Armées Percy, 101, Avenue Henri Barbusse, BP 406, 92141 Clamart Cedex, France. E-mail: firstname.lastname@example.org; Tel: +33 1 41 46 64 40; Fax: +33 1 41 46 64 60
Accepted for publication 19 June 2007
First published online 1 August 2007