Tissue Doppler assessment of diastolic function and relationship with mortality in critically ill septic patients: a systematic review and meta-analysis.

BACKGROUND: Myocardial dysfunction may contribute to circulatory failure in sepsis. There is growing evidence of an association between left ventricular diastolic dysfunction (LVDD) and mortality in septic patients. Utilizing echocardiography, we know that tissue Doppler imaging (TDI) variables e' and E/e' are reliable predictors of LVDD and are useful measurements to estimate left ventricular (LV) filling pressures. METHODS: We conducted a systematic review and meta-analysis to investigate the association of e' and E/e' with mortality of patients with severe sepsis or septic shock. In the primary analysis, we included studies providing transthoracic TDI data for e' and E/e' and their association with mortality. Subgroup analyses were conducted according to myocardial regional focus of TDI assessment (septal, lateral or averaged). Three secondary analyses were performed: one included data from a transoesophageal study, another excluded studies reporting data at a very early (<6 h) or late (>48 h) stage following diagnosis, and the third pooled data only from studies excluding patients with heart valve disease. RESULTS: The primary analysis included 16 studies with 1507 patients with severe sepsis and/or septic shock. A significant association was found between mortality and both lower e' [standard mean difference (SMD) 0.33; 95% confidence interval (CI): 0.05, 0.62; P=0.02] and higher E/e' (SMD -0.33; 95% CI: -0.57, -0.10; P=0.006). In the subgroup analyses, only the lateral TDI values showed significant association with mortality (lower e' SMD 0.45; 95% CI: 0.11, 0.78; P=0.009; higher E/e' SMD -0.49; 95% CI: -0.76, -0.22; P=0.0003). The findings of the primary analysis were confirmed by all secondary analyses. CONCLUSIONS: There is a strong association between both lower e' and higher E/e' and mortality in septic patients.

Myocardial infarction and cerebrovascular accident following non-cardiac surgery: differences in postoperative temporal distribution and risk factors.

BACKGROUND: Myocardial infarction and stroke after non-cardiac surgery are two ominous cardiovascular complications believed to share similar pathophysiological processes. However, the differences in the temporal distribution between them have not been adequately investigated in a large cohort of patients. METHODS AND RESULTS: The preoperative clinical features and daily occurrence of myocardial infarction and stroke were routinely recorded in 36 634 consecutive patients following elective non-cardiac, non-carotid surgery. The preoperative characteristics and postoperative daily distribution of postoperative myocardial infarction and stroke were compared using exponential and linear regressions models. Myocardial infarction and stroke occurred in 122 (0.33%) and 126 (0.34%) patients, respectively, during the first 30 days after surgery. More patients with myocardial infarction had diabetes mellitus and cardiac disease (P = 0.041 and <0.0001, respectively) whereas more patients with stroke were older and female (P = 0.003 and 0.038, respectively). The peak incidence of myocardial infarction was on the day of surgery (43%) and declined exponentially thereafter (F = 725.4, P < 0.0001). However, postoperative stroke best fitted a linear regression with almost even daily distribution (F = 15.9, P = 0.0004). The median time to myocardial infarction was one day [95% confidence interval (95% CI) = 0-2 days] compared with nine days (95% CI = 7-11 days) for stroke. CONCLUSIONS: The peak incidence of postoperative myocardial infarction is early after non-cardiac surgery and declines exponentially thereafter, as opposed to stroke, which occurs at a constant rate during the postoperative period. Myocardial infarction and cerebrovascular accident following non-cardiac surgery differ in their preoperative risk factors, and in the postoperative time-line of their occurrence.

Myocardial infarction after vascular surgery: the role of prolonged stress-induced, ST depression-type ischemia.

OBJECTIVES: The goal of this study was to investigate the nature of the association between silent ischemia and postoperative myocardial infarction (PMI). BACKGROUND: Silent ischemia predicts cardiac morbidity and mortality in both ambulatory and postoperative patients. Whether silent stress-induced ischemia is merely a marker of extensive coronary artery disease or has a closer association with infarction has not been determined. METHODS: In 185 consecutive patients undergoing vascular surgery, we correlated ischemia duration, as detected on a continuous 12-lead ST-trend monitoring during the period 48 h to 72 h after surgery, with cardiac troponin-I (cTn-I) measured in the first three postoperative days and with postoperative cardiac outcome. Postoperative myocardial infarction was defined as cTn-I >3.1 ng/ml accompanied by either typical symptoms or new ischemic electrocardiogram (ECG) findings. RESULTS: During 11,132 patient-hours of monitoring, 38 patients (20.5%) had 66 transient ischemic events, all but one denoted by ST-segment depression. Twelve patients (6.5%) sustained PMI; one of those patients died. All infarctions were non-Q-wave and were detected by a rise in cTn-I during or immediately after prolonged, ST depression-type ischemia. The average duration ofischemia in patients with PMI was 226+/-164 min (range: 29 to 625), compared with 38+/-26 min (p = 0.0000) in 26 patients with ischemia but not infarction. Peak cTn-I strongly correlated with the longest, as well as cumulative, ischemia duration (r = 0.83 and r = 0.78, respectively). Ischemic ECG changes were completely reversible in all but one patient who had persistent new T wave inversion. All ischemic events culminating in PMI were preceded by an increase in heart rate (delta heart rate = 32+/-15 beats/min), and most (67%) of them began at the end of surgery and emergence from anesthesia. CONCLUSIONS: Prolonged, ST depression-type ischemia progresses to MI and is strongly associated with the majority of cardiac complications after vascular surgery.

Preoperative thallium scanning, selective coronary revascularization, and long-term survival after carotid endarterectomy.

BACKGROUND AND PURPOSE: Long-term survival in patients after carotid endarterectomy (CEA) is determined mainly by their concomitant cardiac disease. We tested to determine whether preoperative thallium scanning (PTS) and subsequent selective coronary revascularization (CR), by either percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass grafting (CABG), improve long-term survival after CEA. METHODS: Two hundred twenty-six of 255 consecutive patients (88%) undergoing CEA from 1990 to 1996 had PTS. Those with significant reversible defects on PTS were referred for coronary angiography and possible CR. Patients who had undergone PTS were divided into the following 4 groups: group 1, normal or mild defects on PTS; group 2, moderate-severe fixed and/or reversible defects in patients who did not undergo CR; group 3, patients who had CR secondary to their PTS results; and group 4, patients who had CR in the past that was not related to the PTS. Perioperative data were prospectively recorded, and data on long-term survival and cardiac and neurological complications were collected. RESULTS: Seventy-seven patients (34%) had preoperative coronary angiography, and 42 (19%) had subsequent CR: preoperative PTCA or CABG in 24, combined CEA+CABG in 10, and post-CEA CABG in 8 patients. No deaths resulted from the coronary angiography, CR, or CEA. Six patients had perioperative nonfatal myocardial infarction and 8 had stroke. During the follow-up (40+/-23 months), 47 patients (18%) died, 31 (66%) from cardiac disease and 4 (8.5%) from stroke. Independent predictors of long-term overall mortality were diabetes mellitus, preoperative T-wave inversion on ECG, lower-extremity arterial disease, and history of neurological symptoms [exp(beta)=3. 5, 3.4, 2.5, and 2.4; P=0.0003, 0.0004, 0.01, and 0.04, respectively]. In addition, preoperative moderate-severe thallium defect without CR (group 2) independently predicted long-term cardiac mortality [exp(beta)=2.8; P=0.04]. Patients with preoperative CR (group 3) had long-term survival rate similar to that of group 1 and significantly better than that of group 2 (P=0. 02). CONCLUSIONS: PTS predicts long-term survival, and selective CR based on the thallium results improves the survival rate of patients undergoing CEA.

Step baroreflex response in awake patients undergoing carotid surgery: time- and frequency-domain analysis.

Step baroreceptor stimulation can provide an insight into the baroreflex control mechanism, yet this has never been done in humans. During carotid surgery under regional anesthesia, a step increase in baroreceptor stimulation occurs at carotid declamping immediately after removal of the intra-arterial atheromatous plaque. In 10 patients, the R-R interval and systolic and diastolic blood pressures (BP) were continuously recorded, and signals obtained within the time window from 10 min before until 10 min after carotid declamping were analyzed. Mean +/- SD time signals, power spectra, and transfer and coherence functions before and after declamping were calculated. Immediately after carotid declamping, both heart rate (HR) and BP declined in an exponential-like manner lasting 10.3 +/- 5.9 min, and their power spectra increased in the entire frequency range. Transfer function magnitude and coherence functions between BP and HR increased predominantly in the midfrequency region (approximately 0.1 Hz), with no change in phase function. Thus, in carotid endarterectomy patients, step increase in baroreceptor gain elicits a prolonged decline in HR and BP. Frequency analyses support the notion that the baroreflex control mechanism generates the midfrequency HR and BP variability, although other frequency regions are also affected.

Perioperative ischemia and cardiac complications in major vascular surgery: importance of the preoperative twelve-lead electrocardiogram.

PURPOSE: To investigate the associations between specific preoperative 12-lead electrocardiogram (ECG) abnormalities, perioperative ischemia, and postoperative myocardial infarction or cardiac death in major vascular surgery. METHODS: Two prospective studies on perioperative myocardial ischemia performed in two tertiary university hospitals were combined to include 405 patients. All preoperative ECGs were analyzed according to the Sokolow-Lyon criteria for left ventricular hypertrophy by investigators who were blinded to the patients' perioperative clinical course. Perioperative myocardial ischemia was detected by continuous ECG recording, and postoperative cardiac complications included myocardial infarction and cardiac death. RESULTS: A total of 19 postoperative cardiac complications occurred (two cardiac deaths and 17 myocardial infarctions). Voltage criteria for left ventricular hypertrophy (78 patients, 19%) and ST segment depression greater than 0.5 mm (98 patients, 24.2%) on preoperative ECGs were both significantly associated with postoperative myocardial infarction or cardiac death (odds ratio, 4.2 and 4.7; p = 0.001 and 0.0005, respectively) and with longer intraoperative and postoperative myocardial ischemia. In each of the two study groups, a preoperative ECG abnormality that involved voltage criteria, ST segment depression, or both (134 patients, 33.1%) was more predictive of postoperative cardiac complications than any other preoperative clinical variable, including a history of myocardial infarction or angina pectoris, diabetes mellitus, pathologic Q-wave by ECG, or preoperative myocardial ischemia. The combined duration of intraoperative and postoperative ischemia and the preoperative ECG with either voltage criteria or ST segment depression were the only independent factors associated with adverse cardiac events by multivariate analysis (p < or = 0.0001 and p = 0.02, respectively). CONCLUSION: Left ventricular hypertrophy and ST segment depression on preoperative 12-lead ECGs are important markers of increased risk for myocardial infarction or cardiac death after major vascular surgery.

Prolonged postoperative myocardial ischaemia and infarction in vascular surgery performed under regional anaesthesia.

The importance of prolonged postoperative myocardial ischaemia in cardiac outcome has recently been emphasised. The present study examines the correlation between perioperative ischaemia and myocardial infarction (MI) in patients undergoing peripheral vascular surgery (PVS) under regional anaesthesia. One-hundred-and-forty consecutive peripheral vascular operations under regional anaesthesia were prospectively analysed, using Holter monitoring for perioperative myocardial ischaemia (defined as down sloping or horizontal ST-segment depression of > or = 1 mm) and postoperative cardiac outcome. The study was approved after informed consent. There were 82 carotid endarterectomies under cervical block and 58 infrainguinal bypass procedures under continuous spinal or epidural anaesthesia. IHD was present in 53.6% cases: previous MI-38%; angina pectoris-33%; previous CABG/PTCA-24%. Holter monitoring started about 20 hours before surgery and continued for 45 hours. After surgery patients were followed for signs of cardiac complications; daily 12 lead ECG; 6 hourly CK-MB isoenzymes during the first 24 postoperative hours and later whenever indicated. MI diagnosis was based on chest pain, permanent new ECG changes and CK-MB elevation. There was no 30-day mortality. Postoperative MI occurred in seven patients (5%). Five of the postoperative MI were non-Q-wave infarctions. The majority (71%) of the adverse cardiac events started within 24 hours of surgery, and the latest occurred 52 and 72 hours post surgery. In 65 cases (46.4%) there were 259 episodes of significant ST-depression. In 75 (53.6%) cases ischaemic episodes were not detected. Patients with postoperative cardiac events had significantly more and longer ischaemic episodes in all three perioperative periods than those without such events.(ABSTRACT TRUNCATED AT 250 WORDS)

Perioperative myocardial ischemia in carotid endarterectomy under cervical plexus block and prophylactic nitroglycerin infusion.

Perioperative myocardial ischemia was evaluated in 36 consecutive carotid endarterectomy procedures carried out on patients with a high (72.2%) prevalence of ischemic heart disease. The procedures were performed under cervical plexus block plus a prophylactic intravenous nitroglycerin infusion. Findings of myocardial ischemia on perioperative (48 hours) continuous electrocardiogram recordings were correlated with preoperative cardiac status, perioperative continuous intra-arterial blood pressure measurements, and postoperative cardiac outcome. In two patients, ST segment analysis was un-interpretable because of bundle-branch blocks. Altogether, 64 episodes of significant ST segment depression were detected in 18 (52.9%) of the remaining procedures. In 8 (23.5%) procedures, ST segment depressions occurred either during carotid artery clamping at the time of the largest rise in blood pressure or within 2 hours of declamping, when blood pressure tended to decline. There were four (11.7%) postoperative cardiac events: three myocardial infarctions (one Q wave and two non-Q wave) and one episode of unstable angina pectoris. All four patients with cardiac events had early signs of myocardial ischemia either at the time of cross-clamping, or soon after declamping of the carotid artery. All myocardial infarctions developed following prolonged (> 10 hours) myocardial ischemia, starting with the first 20 hours after surgery. Thus, ST segment depression occurring during clamping or soon after carotid declamping was associated with cardiac complications (sensitivity 100% and specificity 86.6%) and suggests the possible usefulness of on-line ST segment trend monitoring.

Importance of long-duration postoperative ST-segment depression in cardiac morbidity after vascular surgery.

Major vascular surgery is associated with a high incidence of cardiac ischaemic complications. By means of continuous perioperative electrocardiographic recording, we studied 151 consecutive patients undergoing major vascular surgery to find out the characteristics of any myocardial ischaemia and the relation to outcome. 13 (8.6%) patients had postoperative cardiac events (6 myocardial infarctions, 2 unstable angina, and 5 congestive heart failure). There were 342 perioperative ischaemic episodes shown by ST-segment depression; 164 (48%) occurred postoperatively. Postoperative ischaemic episodes were significantly longer than episodes before or during operations (3.2 vs 1.7 and 1.5 min per h monitored, respectively, p < 0.001). Both Detsky's cardiac risk index and long-duration (> 2 h) preoperative ischaemia were predictive of postoperative cardiac complications (odds ratios in univariate analysis 3.3, p = 0.03, and 7.2, p = 0.009, respectively). However, long-duration (> 2 h) postoperative ischaemia was the only factor significantly associated with cardiac morbidity in multivariate logistic regression analysis (odds ratio 21.7, p = 0.001). Long-duration ST-segment depression preceded most (84.6%) postoperative cardiac events, including myocardial infarctions, and no cardiac event was preceded by ST-segment elevation. 5 of the 6 postoperative myocardial infarctions were non-Q-wave infarctions. We conclude that long-duration subendocardial ischaemia, rather than acute coronary artery occlusion, may bring about postoperative myocardial injury and complications.

Carotid-cardiac interaction: heart rate variability during the unblocking of the carotid artery.

Multiresolution representations of the heart rate variability (HRV) using the wavelet transforms are proposed to characterize the autonomic nervous system regulation of cardio-vascular activity during carotid surgery. Results suggest that the power in all frequency bands was low during the surgery and increased after the declamping of the carotid artery.

[Surgical pulmonary embolectomy and thrombolytic therapy].

Acute, massive pulmonary embolism is life-threatening and must be treated immediately. Since the early 1970's when thrombolytic therapy was shown to hasten resolution of pulmonary emboli, there has been a debate in the literature as to new indications for surgical pulmonary embolectomy. Some authors believed that there are no longer any indications for embolectomy, while others justify surgery for certain indications. Although the debate is still on, this operation is very rarely performed today. We present a patient who developed massive pulmonary embolism, with continuing extreme hemodynamic and respiratory disturbances despite full thrombolytic treatment. Embolectomy was successfully performed.

[Intrapleural marcaine for postoperative analgesia].

Intrapleural marcaine has been described as an effective method of analgesia following upper abdominal and thoracic operations and is no longer regarded as experimental. We have shown that the same quality of analgesia can be achieved by injecting the drug through a catheter inserted intraoperatively through the surgical incision. In our method, applied in 9 cases, there is no risk of pneumothorax as a result of piercing the chest wall, since intraoperative placement of the intrapleural catheter is very easy. We therefore suggest it as the method of choice for postoperative analgesia in kidney operations. It is especially recommended in elderly patients with chronic pulmonary disease who do not tolerate narcotics well.