Torsten Toftegård Nielsen

Routine thrombectomy in percutaneous coronary intervention for acute ST-segment-elevation myocardial infarction: a randomized, controlled trial.

Background— Distal embolization during primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction may result in reduced myocardial perfusion, infarct extension, and impaired prognosis. Methods and Results— In a prospective randomized trial, we studied the effect of routine thrombectomy in 215 patients with ST-segment–elevation myocardial infarction lasting <12 hours undergoing primary PCI. Patients were randomized to thrombectomy pretreatment or standard PCI. The primary end point was myocardial salvage measured by sestamibi SPECT, calculated as the difference between area at risk and final infarct size determined after 30 days (percent). Secondary end points included final infarct size, ST-segment resolution, and troponin T release. Baseline variables, including ST-segment elevation and area at risk, were similar. Salvage was not statistically different in the thrombectomy and control groups (median, 13% [interquartile range, 9% to 21%] and 18% [interquartile range, 7% to 25%]; P=0.12), but 24 patients in the thrombectomy group and 12 patients in the control group did not have an early SPECT scan, mainly because of poor general or cardiac condition (P=0.04). In the thrombectomy group, final infarct size was increased (median, 15%; [interquartile range, 4% to 25%] versus 8% [interquartile range, 2% to 18%]; P=0.004). Conclusions— Thrombectomy performed as routine therapy in primary PCI for ST-elevation myocardial infarction does not increase myocardial salvage. The study suggests a possible deleterious effect of thrombectomy, resulting in an increased final infarct size, and does not support the use of thrombectomy in unselected primary PCI patients.

Primary PCI as the preferred reperfusion therapy in STEMI: it is a matter of time

There is a continuing controversy about the acceptable time-window for primary percutaneous coronary intervention (PPCI) in patients with ST-elevation myocardial infarction (STEMI). Recent American and European guidelines recommend PPCI if the delay in performing PPCI instead of administering fibrinolysis (PCI-related delay) is <60 min and the presentation delay is more than 3 h. Based on a review of the literature, this viewpoint recommends a revision of the guidelines. The evidence supports an acceptable PCI-related delay of 80–120 min and PPCI as the better reperfusion strategy also in the early incomers. Furthermore, the previous assumption that PPCI is less time-dependent than fibrinolysis is questioned. To maximise the number of patients with STEMI eligible for PPCI the optimal logistic may be to establish the diagnosis in the prehospital phase, to bypass local hospitals and re-route patients directly to catheterisation laboratories running 24/7.

System Delay and Timing of Intervention in Acute Myocardial Infarction (from the Danish Acute Myocardial Infarction-2 [DANAMI-2] Trial)

The interval from the first alert of the healthcare system to the initiation of reperfusion therapy (system delay) is associated with mortality in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention (pPCI). The importance of system delay in patients treated with fibrinolysis versus pPCI has not been assessed. We obtained data on system delay from the Danish Acute Myocardial Infarction-2 study, which randomized 1,572 patients to fibrinolysis or pPCI. The study end points were 30-day and 8-year mortality. The short system delays were associated with reduced absolute mortality in both the fibrinolysis group (<1 hour, 5.6%; 1 to 2 hours, 6.9%; 2 to 3 hours, 9.5%; and >3 hours, 11.5%; test for trend, p = 0.08) and pPCI group (<1 hour, not assessed; 1 to 2 hours, 2.6%; 2 to 3 hours, 7.5%; >3 hours, 7.7%; test for trend, p = 0.02). The lowest 30-day mortality was obtained with pPCI and a system delay of 1 to 2 hours (vs fibrinolysis within <1 hour, adjusted hazard ratio 0.33; 95% confidence interval 0.10 to 1.10; p = 0.07; vs fibrinolysis within 1 to 2 hours, adjusted hazard ratio 0.37; 95% confidence interval 0.14 to 0.95; p = 0.04). pPCI and system delay >3 hours was associated with a similar 30-day and 8-year mortality as fibrinolysis within 1 to 2 hours. In conclusion, short system delays are associated with reduced mortality in patients with ST-segment elevation myocardial infarction treated with fibrinolysis as well as pPCI. pPCI performed with a system delay of <2 hours is associated with lower mortality than fibrinolysis performed with a faster or similar system delay.

Myocardial infarction centres: the way forward

In the era of primary PCI, a strategy of admitting patients to the nearest hospital should be obsolete. Instead, a prehospital diagnostic strategy should be implemented in order to: (1) refer patients directly to interventional centres, thereby eliminating delay at local hospitals; (2) alert the interventional centre, thereby reducing door to balloon times; (3) initiate adjunctive medication in the prehospital phase

Should patients with acute ST elevation MI be transferred for primary PCI

The treatment strategy for acute myocardial infarction (MI) with ST elevation or newly developed left bundle branch block has been focusing on immediate opening of the infarct related coronary artery. This is because the prognosis for the patient is dependent upon the restoration of coronary flow and myocardial perfusion.1 Numerous randomised controlled trials with thrombolytic drugs have shown that these drugs can preserve left ventricular function and decrease mortality. Therefore treatment with streptokinase, alteplase, reteplase, and tenecteplase, when administered within 12 hours of onset of symptoms, is given the highest recommendation (IA) in guidelines.2 Mechanical reperfusion with percutaneous coronary intervention (PCI) in acute MI (primary or direct PCI) (fig 1) was first performed by Meyer and colleagues and Hartzler and colleagues in the beginning of the 1980s. During the next decade pioneer work, in particular by the Zwolle and the PAMI groups, showed that when performed in centres with great expertise, primary PCI was superior to thrombolytic treatment. Subsequent trials conducted in centres, that were not necessarily staffed by world experts in primary PCI, also showed that in this setting (the real world) primary PCI was better than thrombolytic treatment. In a recent meta-analysis of 23 randomised trials comparing primary PCI and thrombolytic treatment, primary PCI was superior to thrombolysis, when looking at short term mortality (7% v 9%), non-fatal reinfarction (3% v 7%), stroke (1% v 2%), and the combined end point of death, non-fatal re-infarction, and stroke.3 Figure 1  Inferior ST elevation myocardial infarction with total occlusion of the right coronary artery treated with a stent and a distal protection device. In 1999 the American College of Cardiology/American Heart Association guidelines recommended primary PCI as an alternative to thrombolysis. The European guidelines published in 20032 state: “primary PCI is the preferred therapeutic option when it can …

BENEFICIAL EFFECT OF A LOW-FAT LOW-CALORIE DIET ON MYOCARDIAL ENERGY METABOLISM IN PATIENTS WITH ANGINA PECTORIS

8 patients with exertional angina pectoris were treated for 3 months with a low-fat, low-calorie diet. Serum cholesterol was reduced by 28% and body-weight by 7.9 kg on average. The effect of the dietary intervention was assessed by a heart metabolic study during pacing-induced tachycardia. After dietary treatment coronary sinus blood-flow and myocardial oxygen consumption were considerably reduced, but pacing time before angina developed increased. Other improvements were a reduction in lactate release during pacing, a reduction in citrate release during recovery, a reduction in alanine output during rest and recovery, and a lower uptake of glutamate. The results suggest a beneficial effect of low-fat, low-calorie dietary treatment on myocardial energy metabolism in patients with exertional angina pectoris.

Long-term effects of invasive treatment in patients with a post-thrombolytic Q-wave myocardial infarction.

Abstract Objectives. The aim of the present study was to assess the effect of a deferred invasive treatment strategy on long-term outcome in patients with a post-thrombolytic Q-wave myocardial infarction and inducible myocardial ischemia. Design. Patients (N=751) with post-thrombolytic Q-wave myocardial infarction and inducible ischemia (angina pectoris or silent myocardial ischemia) were randomized to a deferred invasive treatment (balloon angioplasty or coronary bypass surgery) or medical treatment. Vital status and non-fatal cardiac events defined as hospitalization caused by acute cardiac events were recorded for a median of 11.4 years. Results. Survival was significantly improved in patients receiving invasive treatment compared to patients treated medically (hazard ratio 0.85 (95% confidence limits 0.73–0.99), p=0.034). Subgroup analysis showed a reduction of non-fatal cardiac events and improved survival among the patients with post-infarction angina pectoris and not among the patients with silent myocardial ischemia. Conclusions. A deferred invasive treatment strategy improves survival compared to medical treatment in patients with inducible myocardial ischemia after a post-thrombolytic Q-wave myocardial infarction.