Mario Vincenzi

Detectable serum troponin I in patients with heart failure of nonmyocardial ischemic origin

Cardiac troponin I, a specific and sensitive marker of myocardial damage, was detected in the blood of 6 of 26 patients studied in our Heart Failure Clinic. In these patients functional class, ventricular function, and prognosis were significantly worse than in those without detectable troponin I. This study suggests that troponin I may represent the biochemical marker of myocardial damage occurring in severe heart failure.

Troponin T, troponin I and creatine kinase-MB mass after elective coronary stenting.

Objective To assess whether and to what extent elective coronary stenting is associated with biochemical evidence of minor myocardial damage (MMD), as defined by the detection of abnormal post-procedural serum levels of one or more among the following markers of ischaemic injury: creatine kinase (CK)-MB mass, troponin T (Tn-T) and troponin I (Tn-I).Methods Nineteen elective procedures of coronary stenting were compared with a matched group of 25 conventional percutaneous transluminal coronary angioplasty (PTCA) procedures performed in our laboratory from March to June 1995. Cases with evolving or recent (< 2 weeks) myocardial infarction, chronic total occlusions and dilatation of saphenous vein grafts were excluded. By definition, all of the patients had undergone uneventful deployment of a single Palmaz-Schatz stent, with no chest pain and no persistent ECG changes after the procedure. Serum levels of CK-MB mass, Tn-T and Tn-I were determined at baseline and 6, 12 and 24 h after the procedure. The frequency of abnormal results was determined for each marker. Baseline and peak post-procedural levels in the two groups were compared and related to procedural variables.Results Baseline values were normal in all cases. The quantitative analysis showed that post-procedural levels of each marker (including total CK) were significantly higher with respect to baseline in both groups. In the stent group, two patients had positive CK-MB mass, four positive Tn-T and seven positive Tn-I. Absolute changes in Tn-T and Tn-I were closely related to changes in CK-MB mass (r = 0.76, P < 0.0001; r = 0.90, P < 0.0001, respectively). Three of these patients developed clinically silent side-branch occlusion. All of them were positive for troponins and two were positive for CK-MB. No correlation was found between procedural variables and the results of biochemical assays. In the PTCA group, three patients were positive for Tn-I, whereas the CK-MB mass and Tn-T remained constantly normal. No side-branch occlusion was observed. The peak CK-MB mass and Tn-I were significantly higher in the stent group than they were in the PTCA group (3.04 ± 4.1 versus 1.27 ± 1.3 ng/ml, P = 0.046; 0.78 ± 1.17 versus 0.28 ± 0.3 ng/ml, P = 0.046, respectively). This difference was no longer apparent when patients with side-branch occlusion were excluded.Conclusions In our series, Tn-I measurement shows the highest ability to detect MMD, being positive in 37% of stent and 14% of PTCA cases. Elective coronary stenting is associated with greater release of CK-MB mass and Tn-I than is conventional PTCA. This finding is mainly determined by cases of side branch occlusion, which account for most, but not all, periprocedural MMD in the stent group.

Ventricular late potentials, interstitial fibrosis, and right ventricular function in patients with ventricular tachycardia and normal left ventricular function

We examined 40 patients with ventricular tachycardia (VT) and no evidence of heart disease, and found a 50% prevalence of ventricular late potentials (VLPs) on the signal-averaged electrocardiogram. This finding was associated with a significantly higher content of fibrous tissue on endomyocardial biopsy and a lower right ventricular ejection fraction. Thus, VLPs are frequently found in idiopathic VT, are a marker for subclinical anatomic and functional abnormalities of the right ventricle, and may be associated with a worse outcome.

Rescue PTCA for a Totally Occluded Left Main Coronary Artery in Acute Myocardial Infarction with Cardiogenic Shock: Technical Success and Long-Term Survival

Percutaneous transluminal coronary angioplasty was performed after failed thrombolysis in a 54-year-old man for total occlusion of the left main coronary artery in the setting of acute myocardial infarction with cardiogenic shock. The procedure was successful in terms of vessel recanalization and restoration of flow. The recovery of muscle function was limited due to the time lag between onset of symptoms and recanalization. This case highlights the crucial role of early identification and prompt referral of patients with extensive ischemia to centers with the capability for emergency percutaneous revascularization procedures.

Radiofrequency Catheter Ablation of the Slow Reentrant Pathway of Sustained Ventricular Tachycardia

The article reports the cases of two patients with severe coronary artery disease and associated recurrent sustained ventricular tachycardia successfully treated with radiofrequency catheter ablation. In the first patient, two different types of ventricular tachycardia (one incessant) were eliminated. In all procedures, an area of slow conduction critical for tachycardia maintenance was localized by endocardial mapping techniques. Radiofrequency energy delivered to this area could permanently modify the anatomical substrate of the arrhythmia. After single follow‐ups of 19, 14, and 13 months regarding the arrhythmic entities, the patients are well and free from spontaneous recurrences.

Multicenter clinical evaluation of a new SSIR pacemaker.

A multicenter clinical evaluation of Sorin Swing 100, a new SSIR pacemaker with a gravimetric sensor, was performed by seven different centers enrolling a total of 89 patients, 56 men and 33 women, mean age 73.1 years, for pacemaker implantion (73 patients) or pacemaker replacement (16 patients). Pacing mode was VVIR in 73 patients and AAIR in 16. The behavior of pacing rate was evaluated 3 months after the implant by performing a 24‐hour Holter monitor, an exercise stress test, and tests for the assessment of mechanical external interference (MEI). A physiological behavior of the paced rate was always observed during Holter monitoring. In 52 completely paced patients mean diurnal, nocturnal, and maximal heart rate were, respectively, 74.9 ± 5.7 ppm, 58.1 ± 5.8 ppm, and 113.4 ± 12.7 ppm; a paced rate exceeding 100 ppm was reached on the average 5.6 times/Holter monitor. In all but two patients the sleep rate (55 ppm) was reached during the night or long resting time. During exercise stress test a direct correlation between the increase in pacing rate and the increase in workload was observed; the mean maximal heart rate reached in 49 completely paced patients was, respectively, 102.8 ± 9 ppm in 17 patients who accomplished stage 1, 116.2 ± 13.6 ppm in 28 patients who accomplished stage 2, and 133 ± 6.7 ppm in 10 patients who accomplished stage 3 of the Bruce protocol. MEI testing never increased the pacing rate over the noise rate (10 ppm over the basic rate). In only seven patients the results obtained suggested to change the nominal set up of the pacemaker. Our experience clearly indicates that Swing 100 is an effective, reliable, and easy to use SSIR pacemaker. The availability of the sleep rate allows a more physiological pattern of pacing rate and can lead to significant energy saving.