Alberto Cappelletti

Specificity and sensitivity of exercise-induced ST segment elevation for detection of residual viability : comparison with fluorodeoxyglucose and positron emission tomography

OBJECTIVES We evaluated the sensitivity and specificity of exercise-induced ST segment elevation for the detection of residual myocardial viability. BACKGROUND Assessment of residual viability after myocardial infarction is relevant for establishing indication for revascularization. We have previously shown that exercise-induced ST segment elevation is a marker of residual viability. METHODS We studied 34 patients with a previous Q wave myocardial infarction (anterior in 21, inferior in 13) of whom 18 (group A) had exercise-induced ST segment elevation in more than one lead (mean [+/- SD] 1.8 +/- 0.9 mm, range 1 to 4) and 16 (group B) did not. All patients underwent rest technetium-99m methoxyisobutyl isonitrile single-photon emission computed tomography (SPECT), fluorine-18 (F-18) fluorodeoxyglucose positron emission tomography and coronary angiography. The time elapsed between the infarction and the viability study was 72 +/- 108 days (range 15 to 400) in group A and 516 +/- 545 days (range 14 to 1,800) in group B. RESULTS The presence and site of previous infarction were confirmed by SPECT studies in all 34 patients. Uptake of F-18 fluorodeoxyglucose within the infarcted area was present in 18 of 18 patients in group A but in only 9 (56%) of 16 in group B (p < 0.01). In patients with an anterior infarction, the sensitivity, specificity and predictive accuracy of exercise-induced ST segment elevation for detection of residual viability were 82%, 100% and 86%, respectively (95% confidence intervals 46% to 83.5%, 59% to 100% and 55.6% to 87.1%, respectively). CONCLUSIONS Exercise-induced ST segment elevation in infarct-related leads has a high specificity and acceptable sensitivity for detection of residual viability within the infarcted area.

Coronary Recanalization by Elective Angioplasty Prevents Ventricular Dilation After Anterior Myocardial Infarction

OBJECTIVES In a prospective study we evaluated whether late recanalization of the left anterior descending coronary artery (LAD) affects ventricular volume and function after anterior myocardial infarction. BACKGROUND Persistent coronary occlusion after anterior myocardial infarction leads to ventricular dilation and heart failure. METHODS We studied 73 consecutive patients with acute anterior myocardial infarction as a first cardiac event; all had an isolated lesion or occlusion of the proximal LAD. Six patients died before hospital discharge. The 67 survivors were classified into two groups: group I (patent LAD and good distal flow, n = 40) and group II (LAD occlusion or subocclusion, n = 27). The 20 patients in group I who had significant residual stenosis and all patients in group II underwent elective percutaneous transluminal coronary angioplasty (PTCA) within 18 days of myocardial infarction. The procedure was successful in 17 patients in group I (group IB) and in 16 patients in group II (group IIA): in the remaining 11 patients of group II, patency could not be reestablished (group IIB). Left ventricular volumes, ejection fraction and a dysfunction score were measured by echocardiography on admission, before PTCA, at discharge and after 3 and 6 months. RESULTS Although cumulative ST segment elevation was similar in groups I and II, ejection fraction and dysfunction score were significantly worse in group II. However, ventricular function and volumes progressively improved in group IIA, whereas group IIB exhibited progressive deterioration of function (dysfunction score [mean +/- SD] increased from 21 +/- 6 to 25 +/- 8, p < 0.05; ejection fraction decreased from 43 +/- 10% to 37 +/- 11%, p < 0.05); and end-systolic volume increased from 34 +/- 10 to 72 +/- 28 ml/m2, p < 0.05). Patients in group IIB also had worse effort tolerance, higher heart rate at rest, lower blood pressure and significantly greater prevalence of chronic heart failure. CONCLUSIONS Delayed PTCA of an occluded LAD can frequently restore vessel patency. Success appears to be associated with better ventricular function and a lack of chronic dilation. Large randomized studies are warranted to evaluate the effect of delayed PTCA on late mortality.

Assessment of residual tissue viability by exercise testing in recent myocardial infarction: Comparison of the electrocardiogram and myocardial perfusion scintigraphy

The assessment of residual myocardial viability in infarcted areas is relevant for subsequent management and prognosis but requires expensive technology. To evaluate the possibility that simple, easily obtainable clinical markers may detect the presence of within-infarct viable tissue, the significance of exercise-induced ST elevation occurring in leads exploring the area of a recent Q wave myocardial infarction was assessed. Twenty-five patients with recent (less than 6 months) myocardial infarction were studied. All had angiographically documented coronary artery disease, diagnostic Q waves (n = 24) or negative T waves (n = 25) on the rest 12-lead electrocardiogram and exhibited during exercise greater than or equal to 1.5 mm ST segment elevation (n = 17) or isolated T wave pseudonormalization (n = 8) in the infarct-related leads. ST-T wave changes were reproduced in all patients during thallium-201 exercise myocardial scintigraphy. A fixed perfusion defect was observed in 24 of the 25 patients. A reversible defect was seen in 16 (94%) of 17 patients who exhibited transient ST elevation during exercise but in only 4 (50%) of the 8 patients who had only T wave pseudonormalization. In conclusion, in patients with recent myocardial infarction, analysis of simple ST segment variables obtained during exercise testing may allow a first-line discrimination of those who may potentially benefit from a revascularization procedure.

Predictors of cardiac death in patients with coronary chronic total occlusion not revascularized by PCI

BACKGROUND Limited data are available on clinical outcome of patients with previously failed or not attempted chronic total occlusion (CTO) recanalization by percutaneous coronary intervention (PCI). The aim of the study is to determine prevalence and predictors of cardiac death in patients with CTO not revascularized by PCI. METHODS Double-center study analyzing data of 1.345 consecutive patients with at least one CTO between 1998 and 2008. Of these, 847 patients were successfully revascularized (Revascularized group) and 498 patients were not revascularized (Not revascularized group) either due to failure of CTO-PCI (n=337) or because no attempt was made (n=161). RESULTS At 4-year clinical follow-up, Not revascularized patients had a significantly higher rate of cardiac mortality (8.5% vs. 2.5%, p<0.0001) and sudden cardiac death (2.7% vs. 0.5%, p=0.001) compared to those Revascularized. The separate adjusted Cox-model analysis made for Not revascularized patients showed the most significant independent predictors of cardiac death were: chronic renal failure [HR (CI), 6.0 (2.66-13.80)], low-LVEF [5.7 (2.84-11.58)], insulin-dependent diabetes mellitus (IDDM) 4.6 [(1.96-10.97)]. In the Revascularized group, the presence of 3-vessel disease was the only significant independent predictor of cardiac death [4.4 (1.40-13.70)]. CONCLUSIONS CTO patients Not revascularized had a significant higher rate of cardiac mortality and sudden cardiac death compared to those Revascularized. Within Not revascularized patients, the presence of low-LVEF, or CRF or IDDM was associated with an incidence of cardiac death at least 4 times higher than those without the same risk factors.

Short- and Long-Term Evolution of Unstented Nonocclusive Coronary Dissection After Coronary Angioplasty

OBJECTIVES We assessed the short- and long-term clinical and angiographic outcome of nonocclusive unstented dissection after percutaneous transluminal coronary angioplasty (PTCA) and its correlation with restenosis. BACKGROUND The use of stents has dramatically increased both the number and the cost of coronary revascularization procedures. However, this technique is not completely risk free, and its benefits have not been fully demonstrated in uncomplicated dissections. METHODS We studied 129 consecutive patients with 49 nonocclusive dissections after PTCA (grades A to D of National Heart, Lung, and Blood Institute classification) and good distal flow (TIMI [Thrombolysis in Myocardial Infarction] flow grade 3). All patients underwent coronary angiography at 24 h and at six months post-PTCA. Clinical status was assessed every three months in the outpatient clinic. Study subjects were matched with 60 other patients in whom stenting was performed for the presence of dissection. RESULTS In the former group, all but two patients (with type E dissection, which evolved to coronary occlusion and myocardial infarction) improved their dissection score during follow-up: at six months only 18 dissections were still angiographically visible, and no clinical adverse events were recorded. In the dissected vessels, the restenosis rate was significantly lower than in those without dissection (12% vs. 44%, p < 0.001); in the stented vessels, the restenosis rate was 25% (15/60). CONCLUSIONS In the presence of TIMI flow grade 3, coronary dissection is associated with a favorable outcome and predicts a low restenosis rate. These results caution against the indiscriminate use of intravascular prostheses in the event of nonocclusive coronary dissection.

Enoximone Echocardiography for Predicting Recovery of Left Ventricular Dysfunction After Revascularization A Novel Test for Detecting Myocardial Viability

BACKGROUND The possibility that enoximone, a nonglycoside, noncatechol, positive inotropic agent, in combination with 2-dimensional echocardiography may predict recovery of myocardial dysfunction after revascularization has not been yet evaluated. METHODS AND RESULTS Forty-five patients with chronic coronary artery disease and left ventricular dysfunction underwent dobutamine (DE, 5 to 10 microg. kg(-1). min(-1)) and enoximone (EE, 1.5 mg/kg, over 10 minutes) echocardiography. Myocardial wall motion was scored from 1 (normal) to 4 (dyskinesia): an asynergic segment was considered to have contractile enhancement when the score decreased by >/=1 grade. Of 478 asynergic segments, 216 (45%) exhibited functional recovery after revascularization. Dobutamine- and enoximone-induced contractile enhancement was observed in 41% and 46% of segments, respectively. Compared with DE, EE had higher sensitivity (88% versus 79%, P<0.01) and negative predictive value (90% versus 84%, P<0.05) in predicting functional recovery. The specificity (89% versus 90%) and positive predictive value (87% for both EE and DE) were similar. Concordant interpretation of EE and DE findings was found in 85% (406 of 478) of affected segments. Prerevascularization coronary angiography showed that stenosis severity of vessels supplying areas which only improved with enoximone was significantly greater (89.9%) than that of vessels (77.7%) supplying areas that responded to both agents (P<0.02). Both dobutamine and enoximone increased heart rate (16% and 10%, respectively), whereas enoximone did not cause changes in systolic blood pressure that increased by 14% with dobutamine. CONCLUSIONS Enoximone echocardiography provides a novel and reliable approach for the prediction of functional recovery after revascularization. Compared with dobutamine echocardiography, the test yields higher sensitivity and induces lesser hemodynamic alterations.

Coronary collaterals reduce the duration of exercise-induced ischemia by allowing a faster recovery

The role of collaterals in influencing postischemic recovery after exercise testing has not been investigated previously. We studied 54 patients (mean age 59 +/- 6 years) with effort-induced angina and documented coronary disease who underwent exercise testing and thallium-201 myocardial scintigraphy. On angiography, 30 patients (group A) exhibited visible collaterals (grade 2 to 3, Cohen and Rentrop classification) perfusing the ischemic zone, whereas the other 24 (group B) did not. Patients with collaterals had more severe coronary artery disease (Gensini score 46.9 +/- 16 vs 28.6 +/- 18; p less than 0.001) and more severe impairment of coronary flow reserve (time and rate-pressure product to 1 mm ST segment depression 3.5 +/- 0.8 vs 4.8 +/- 0.6 minutes, p less than 0.01; 14,189 +/- 2451 vs 16,081 +/- 2215 beats/min x mm Hg, p less than 0.04, respectively). However, in these patients the ECG returned to baseline more rapidly after exercise (5.5 +/- 1.6 vs 11.7 +/- 3.3 minutes; p less than 0.001). Therefore, although collaterals do not apparently prevent or delay the development of exercise-induced ischemia, they can limit its duration by allowing a faster recovery.

Prognostic role of stress/rest myocardial perfusion scintigraphy in patients with cardiac syndrome x

AIM The prognostic utility of myocardial perfusion scintigraphy (MPS) in patients with angiographically normal coronary arteries has not been evaluated yet. Our aim was to determine the prognostic role of positive MPS in patients with angina, positive exercise test and smooth coronary arteries (syndrome X). METHODS A total of 156 patients with angina, positive exercise test, positive MPS and normal coronary arteries and 172 patients with angina and positive exercise test who had negative MPS were selected for study. The primary endpoint was combined all-cause mortality and hospitalizations for cardiac causes. The secondary endpoint was hospitalization for cardiac causes. RESULTS Kaplan-Meier analysis showed a greater (p=0.001) incidence of the primary endpoint in patients with positive MPS, compared to those with negative MPS. Additionally, Kaplan-Meier analysis for cardiovascular hospitalization showed a significant difference (p=0.003) between the two groups. Cox regression analysis, adjusted for age, sex, BMI and antianginal therapy confirmed a significant risk increase for patients with positive MPS, with a hazard ratio (HR)=3.20 (CI 95%: 1.14-9.02; p=0.028). Cox analysis for cardiovascular hospitalization also showed a significant risk increase for patients with positive MPS (HR=3.19; CI 95%: 1.13-9.00; p=0.03). Finally, Cox analysis showed that patients with positive MPS tend to have a higher risk to remain symptomatic in the follow-up period (HR=1.614; CI 95%: 0.999-2.607; p=0.51). CONCLUSIONS This study shows that inducible myocardial hypoperfusion at MPS in patients with syndrome X could discriminate patients with a more severe prognosis, especially in terms of further hospitalization and symptomatic burden.

Midterm and one-year outcome of amphilimus polymer free drug eluting stent in patients needing short dual antiplatelet therapy. Insight from the ASTUTE registry (AmphilimuS iTalian mUlticenTer rEgistry)

BACKGROUND To assess clinical outcomes of patients needing short dual antiplatelet therapy (S-DAPT) after PCI with Cre8 polymer-free amphilimus eluting-stent (AES). The Cre8-AES with pure i-Carbofilm coating was supposed to induce faster stent endothelialization and reduce device thrombogenicity. METHODS We performed a sub-analysis of unrestricted consecutive patients treated with Cre8-AES between August 2011 and January 2015. Two groups were formed: 1) patients discharged with S-DAPT (≤3-month), because of high bleeding risk or attending urgent non-cardiac surgery; and 2) patients discharged with Recommended DAPT duration (R-DAPT; ≥6-month). The primary ischemic- and bleeding-safety endpoints were Target Vessel Failure (TVF, composite endpoint of cardiac-death, target vessel-myocardial infarction and target vessel-revascularization), and major-bleeding (BARC ≥type-3a) at 6-month and 1-year. RESULTS 106 patients (8.7%) were discharged with ≤3-month DAPT (83±19days; S-DAPT group) and 1102 patients (90.6%) with ≥6-month DAPT (342±62days; R-DAPT group). Between S-DAPT and R-DAPT groups no significant differences were observed in TVF at 1-year (5.7% vs 5.1%); 1-year BARC major bleeding rate was higher in S-DAPT group (3.4% vs 0.2%, p=0.007) with all bleeding events occurred within 3months. The landmark analysis (started at 90days, ended at 1year) showed no differences in BARC major bleedings between groups (0% vs. 0.3%). CONCLUSIONS The results of this multicenter registry show that the use of Cre8 AES in patients needing short DAPT (≤3-month) was safe regarding ischemic events and could favor a reduction of bleeding events related to the recommended DAPT. A large randomized trial is necessary to support these preliminary findings.

Usefulness of contrast-enhanced transoesophageal echocardiography to guide thoracic endovascular aortic repair procedure

AIMS Thoracic endovascular aortic repair (TEVAR) is commonly considered as a valid alternative to surgery. Endoleaks occurrence is one of the principal limitations of TEVAR. Transoesophageal echocardiography (TEE) is often adopted in adjunct to fluoroscopy and angiography (ANGIO) during stent-graft implantation. In the present study, we compare intraprocedural ANGIO, TEE, and contrast-enhanced TEE (cTEE), and we also evaluate their accuracy in early endoleaks detection and characterization. METHODS AND RESULTS Fifty-four patients with thoracic aortic disease suitable for TEVAR were prospectively enrolled in the study. After stent placement, the result of the procedure was assessed by ANGIO, TEE, and cTEE. The use of contrast (Sonovue, Bracco) significantly improved TEE quality (P = 0.0001). cTEE was superior in entry tears, false and true lumen and aneurysm thrombosis identification, and microtears and ulcer-like projections detection before stent deployment. After stent deployment, cTEE was more accurate than TEE and ANGIO in the detection of slow flow in the false lumen and in the aneurismal sac (P = 0.0001), and in the remaining flow identification (P = 0.0001). Notably, cTEE is more accurate in the endoleaks detection (P = 0.0001) and in the incomplete stent expansion diagnosis and need for a further balloon inflation (P 0.002), or a further stent implantation (P 0.006), compared with TEE and ANGIO. CONCLUSION TEVAR procedures are improved by the complimentary use of contrast fluoroscopy, multiplane TEE with Doppler flow interrogation, and cTEE. This triple imaging approach provides additional information in all phases of the procedure improving safety of stent-grafting and the procedural outcomes.