Cardioprotective role of remote ischemic periconditioning in primary percutaneous coronary intervention: enhancement by opioid action

OBJECTIVES

We sought to determine the potential of remote ischemic periconditioning (RIPC), and its combination with morphine, to reduce reperfusion injury in primary percutaneous coronary interventions.

BACKGROUND

Remote ischemic post-conditioning is implemented by applying cycles of ischemia and reperfusion on a remote organ, which result in release of circulating factors inducing the effects of post-conditioning on the myocardium.

METHODS

A total of 96 patients (59 men) were enrolled. The patients were randomized to groups as follows: 33 to each treatment group (Group A: RIPC; Group B: RIPC and morphine) and 30 to the control group (Group C). Measures of efficacy were achievement of full ST-segment resolution (primary), and reduction of ST-segment deviation score and peak troponin I during hospitalization.

RESULTS

A higher proportion of patients in Groups A (73%) and B (82%) achieved full ST-segment resolution after percutaneous coronary intervention, compared with control patients (53%) (p = 0.045). Peak troponin I was lowest in Group B, 103.3 +/- 13.3 ng/ml, in comparison to peak levels in Group A, 166.0 +/- 28.0 ng/ml, and the control group, 255.5 +/- 35.5 ng/ml (p = 0.0006). ST-segment deviation resolution was 87.3 +/- 2.7% in Group B, compared with 69.9 +/- 5.1% in Group A and 53.2 +/- 6.4% in the control group (p = 0.00002). In paired comparisons between groups, Group B did better than the control group in terms of both ST-segment reduction (p = 0.0001) and peak troponin I (p = 0.004), whereas Group A differences from the control group did not achieve statistical significance (p = 0.054 and p = 0.062, respectively).

CONCLUSIONS

These findings demonstrate a cardioprotective effect of RIPC and morphine during primary percutaneous coronary intervention for the prevention of reperfusion injury. This is in agreement with observations that the beneficial effect of RIPC is inhibited by the opioid receptor blocker naloxone.

Intracardiac echocardiography imaging of periprosthetic valvular regurgitation

A 62-year-old woman was referred for evaluation of recent-onset dyspnoea at rest and a newly found systolic heart murmur, heard best at the apex of the heart. The patient's history was notable for surgical mitral valve replacement 3 years ago, due to severe mitral regurgitation (myxomatous degeneration of the mitral valve). The transthoracic echocardiogram gave the impression of a mitral regurgitant jet, but the acoustic shadow of the prosthesis did not allow adequate evaluation of the regurgitation. A transoesophageal echocardiogram was performed showing a normally functioning mitral prosthesis, with a small periprosthetic leak (Figure 1, upper panel), disproportionate to the patient's symptoms and marked signs of haemolysis. An intracardiac ultrasound study revealed a large paravalvular regurgitant jet, indicating significant periprosthetic regurgitation (Figure 1, lower panel). Intracardiac echocardiography is increasingly being used to guide percutaneous interventions and electrophysiological procedures. The present case suggests a potentially useful widening of the range of intracardiac ultrasound clinical applications, out of the realm of device-closure interventions and electrophysiological procedures. It appears that intracardiac echocardiography could become a second-line alternative to transoesophageal echocardiography, especially in patients with contraindication to the latter.

Effect of radiographic contrast media on markers of complement activation and apoptosis in patients with chronic coronary artery disease undergoing coronary angiography

The effects of radiographic contrast media on markers of complement activation and apoptosis in patients with chronic coronary artery disease (CAD) are unknown. The purpose of this study was to assess the comparative effects of ionic high-osmolar and non-ionic iso-osmolar radiographic contrast media on plasma markers of complement activation and apoptosis in patients with chronic CAD undergoing coronary angiography. Forty-four patients undergoing coronary angiography for chronic CAD were randomly assigned to receive the ionic high-osmolar radiographic contrast agent diatrizoate (Group A), or the non-ionic iso-osmolar contrast agent iodixanol (Group B) during angiography. Complement component 5 (C5a) and apoptotic markers sFas and sFasL were measured just prior to angiography and 1 hour after completion of angiography. Comparison of mean pre- and post-angiography plasma marker levels showed significantly greater increases in plasma levels in Group A than in Group B of C5a (29.30 +/- 5.45 ng/ml for Group A and 0.47 +/- 0.70 ng/ml for Group B (p < 0.00001), sFas (2.36 +/- 1.63 ng/ml for Group A and 0.23 +/- 0.90 ng/ml for Group B (p < 0.00001) and sFasL (14.00 +/- 5.41 pg/ml for Group A and 0.01 +/- 1.00 pg/ml for Group B (p < 0.00001). The results suggest that in patients with chronic CAD, the use of ionic high-osmolar radiographic contrast media during coronary angiography is associated with a more robust inflammatory and apoptotic milieu than that associated with the use of non-ionic iso-osmolar radiographic contrast media.

Acute inferior ST-segment elevation myocardial infarction treated with primary angioplasty using only a Pronto aspiration catheter

In a patient with acute myocardial infarction treated with primary angioplasty, a large amount of thrombus was removed from the middle segment of the right coronary artery using a Pronto V3 extraction catheter (Vascular Solutions, Inc., Minneapolis, Minnesota). Repeat angiography revealed no significant residual stenosis and no further intervention was undertaken.