Impact of Contrast-Associated Acute Kidney Injury on One-Year Outcomes in Very Elderly STEMI Patients: Insights From a Multicenter Registry in Northern Italy.

Data about contrast-associated acute kidney injury (CA-AKI) in oldest old (age ≥85 years) ST-elevation myocardial infarction (STEMI) patients are scarce. We evaluated the incidence and the 1-year prognostic impact of CA-AKI in this population. Patients were included in a multicenter real-world registry, and CA-AKI was defined according to KDIGO (Kidney Disease Improving Global Outcomes) criteria. Major adverse cardiac and cerebrovascular events (MACCEs) were defined as the composite of all-cause death, stroke, unplanned coronary revascularization, and heart failure hospitalization. The primary outcome was the incidence and impact of CA-AKI on MACCEs at 1 year follow-up. Out of 461 STEMI patients (mean age 88.6 ± 2.9 years), 102 (22.1%) patients developed CA-AKI. Chronic kidney disease was the strongest predictor of CA-AKI (odds ratio [OR]: 4.52, 95% CI: 2.81-7.30, P < .01). The CA-AKI cohort showed a higher risk of MACCEs (adjusted HR: 1.75, 95% CI: 1.13-2.71, P = .01), driven mainly by all-cause death (adjusted hazard ratio [HR]: 2.39, 95% CI: 1.41-4.07, P = .01) and followed by heart failure hospitalization (adjusted HR: 2.01, 95% CI: 1.08-3.76, P = .01). Among oldest old STEMI, CA-AKI was frequent and associated with a higher incidence of MACCEs at 1-year follow-up.

Combination of computed tomography angiography with coronary artery calcium score for improved diagnosis of coronary artery disease: a collaborative meta-analysis of stable chest pain patients referred for invasive coronary angiography.

OBJECTIVES: Coronary computed tomography angiography (CCTA) has higher diagnostic accuracy than coronary artery calcium (CAC) score for detecting obstructive coronary artery disease (CAD) in patients with stable chest pain, while the added diagnostic value of combining CCTA with CAC is unknown. We investigated whether combining coronary CCTA with CAC score can improve the diagnosis of obstructive CAD compared with CCTA alone. METHODS: A total of 2315 patients (858 women, 37%) aged 61.1 ± 10.2 from 29 original studies were included to build two CAD prediction models based on either CCTA alone or CCTA combined with the CAC score. CAD was defined as at least 50% coronary diameter stenosis on invasive coronary angiography. Models were built by using generalized linear mixed-effects models with a random intercept set for the original study. The two CAD prediction models were compared by the likelihood ratio test, while their diagnostic performance was compared using the area under the receiver-operating-characteristic curve (AUC). Net benefit (benefit of true positive versus harm of false positive) was assessed by decision curve analysis. RESULTS: CAD prevalence was 43.5% (1007/2315). Combining CCTA with CAC improved CAD diagnosis compared with CCTA alone (AUC: 87% [95% CI: 86 to 89%] vs. 80% [95% CI: 78 to 82%]; p < 0.001), likelihood ratio test 236.3, df: 1, p < 0.001, showing a higher net benefit across almost all threshold probabilities. CONCLUSION: Adding the CAC score to CCTA findings in patients with stable chest pain improves the diagnostic performance in detecting CAD and the net benefit compared with CCTA alone. CLINICAL RELEVANCE STATEMENT: CAC scoring CT performed before coronary CTA and included in the diagnostic model can improve obstructive CAD diagnosis, especially when CCTA is non-diagnostic. KEY POINTS: • The combination of coronary artery calcium with coronary computed tomography angiography showed significantly higher AUC (87%, 95% confidence interval [CI]: 86 to 89%) for diagnosis of coronary artery disease compared to coronary computed tomography angiography alone (80%, 95% CI: 78 to 82%, p < 0.001). • Diagnostic improvement was mostly seen in patients with non-diagnostic C. • The improvement in diagnostic performance and the net benefit was consistent across age groups, chest pain types, and genders.

SUOH 03 Guidewire for the Management of Coronary Artery Dissection: Insights from a Multicenter Registry.

Background: In the setting of coronary artery dissection, both spontaneous and iatrogenic, fixing the intimal tear, usually with stent implantation, can be extremely challenging if the distal wire position has been lost. Common complications are mainly related to the inadvertent subintimal tracking of the guidewire while attempting to gain the distal true lumen. Aims: To report the registry results of using the SUOH 0.3 guidewire for managing coronary artery dissection in a real-world multicenter setting. Methods: The study population in this retrospective, multicenter, international registry included 75 consecutive patients who underwent PCI and required an antegrade wiring of a dissected coronary artery. Results: Successful use of SUOH 0.3 was achieved in 69 (92%) patients. The use of a microcatheter was associated with a significantly higher rate of TIMI 3 flow at the end of the procedure (no microcatheter: n = 17, 81%; microcatheter: n = 52, 96.3%; p = 0.017). The first recanalization attempt was made with the SUOH 03 guidewire in 48 (64%) cases, and it was successful in 42 (87%). The overall PCI success rate was reported in 72 (96%) patients, with no significant differences among patients with different origins, mechanisms, and locations of dissection. Conclusions: In this setting, the SUOH 0.3 guidewire provides high procedural success without additional complex techniques.

Appropriate use criteria of left atrial appendage closure devices: latest evidences.

Atrial fibrillation is the most common arrythmia and it is linked to an increased risk of stroke. Even if anticoagulation therapy reduces the rate of stroke the benefits of this therapy have to be balanced with the increased risk of hemorrhagic event. Left atrial appendage closure is a valid alternative to long-term anticoagulation in patients with atrial fibrillation and high hemorrhagic risk. Actually new devices with different features have been tested and introduced progressively in the clinical practice. Improvements in preprocedural imaging evaluation and the learning curve of the operators led to percutaneous left atrial appendage closure a safe and effective procedure. A good knowledge of different devices and the technique of implant is necessary for optimization percutaneous left atrial appendage closure and the reduction of complications during the acute phase and follow up.

Implementation of a Night Service of Helicopter Transportation to Reduce the Time to Revascularization in STEMI Patients in a Mountainous Region: Impact on Outcomes.

Background: Treatment delays are the most easily audited index of quality of care in the setting of ST-segment elevation myocardial infarction; among the components of ischemia time, system delay has been demonstrated to be a predictor of outcomes, and in a mountainous region it relies mostly upon helicopter rescue service. Aim: The aim of the study is to analyze the impact of the activation of helicopter rescue service for the nighttime for urgent transportation of patients on the time to revascularization and on the outcomes of STEMI patients. Methods: Data were prospectively collected in a database and retrospectively split into two different cohorts, based on the presentation date in the 18 months before, or after, the first day of implementation of the new organizational model. The patients were also split into two groups based on the place of STEMI diagnosis, either the chief town territory or the rest of the region, and retrospectively evaluated for vital status at 30 days and 2 years after index event. Results: The number of patients included was 751. For patients coming from outside Trento, an improvement in ST-segment resolution was shown (ST-segment elevation reduction >50% in 54.0% of the patients vs. 36.4%, p < 0.01). Moreover, a reduction in diagnosis-to-reperfusion median time has been demonstrated (from 105 to 97 min, p < 0.01), mainly driven by a reduction during the night shift (from 119 to 100 min, p = 0.02). With regard to 30-day and 2-year mortality, no statistically significant differences were achieved. Discussion: The organizational effort has translated into a significant reduction in the treatment delay for patients coming from outside the chief town. However, although a longer diagnosis to reperfusion time has been related to a higher mortality, a significant reduction in mortality was not demonstrated in our study. However, an improvement in ST-segment elevation resolution was shown for patients coming from outside the city of Trento, a result that could have other potential clinical benefits. Conclusions: Implementation of night flight proved to be effective in reducing the time between the diagnosis and the treatment of patients in the setting of STEMI, improving ST-segment elevation resolution, although no impact was shown on short- and long-term mortality.

Use of cangrelor in patients with acute coronary syndromes undergoing percutaneous coronary intervention: Study design and interim analysis of the ARCANGELO study.

BACKGROUND: The itAlian pRospective Study on CANGrELOr (ARCANGELO) was aimed to assess the safety of using cangrelor during percutaneous coronary intervention (PCI) in patients with acute coronary syndromes (ACS) in the daily practice. HYPOTHESIS: The safety of cangrelor after the transition to oral P2Y12 inhibitors was evaluated as the incidence of bleeding outcomes in the 30 days following PCI according to postauthorization safety study guidelines. METHODS: Adults with ACS who were treated with cangrelor in one of the 28 centers involved in the study. Patients who consented to participate were followed in the 30 days following their PCI. Bleedings (Bleeding Academic Research Consortium [BARC] classification), major adverse cardiac events (MACEs), and adverse events were recorded. The interim results at two-thirds of the enrollment period are presented. RESULTS: A total of 17 bleedings were observed in the 320 patients who completed the study at this stage. All bleedings were classified as BARC Type 1-2, except for one case of Type 3a (vessel puncture site hematoma). Four patients experienced MACEs (2 acute myocardial infarctions, 1 sudden cardiac death, 1 noncardiovascular death due to respiratory distress, and multiorgan failure). None of the bleedings was rated as related to cangrelor. CONCLUSIONS: The interim results of the ARCANGELO study provide a preliminary confirmation that the use of cangrelor on patients with ACS undergoing PCI is not associated with severe bleedings.

Computed tomography angiography versus Agatston score for diagnosis of coronary artery disease in patients with stable chest pain: individual patient data meta-analysis of the international COME-CCT Consortium.

OBJECTIVES: There is conflicting evidence about the comparative diagnostic accuracy of the Agatston score versus computed tomography angiography (CTA) in patients with suspected obstructive coronary artery disease (CAD). PURPOSE: To determine whether CTA is superior to the Agatston score in the diagnosis of CAD. METHODS: In total 2452 patients with stable chest pain and a clinical indication for invasive coronary angiography (ICA) for suspected CAD were included by the Collaborative Meta-analysis of Cardiac CT (COME-CCT) Consortium. An Agatston score of > 400 was considered positive, and obstructive CAD defined as at least 50% coronary diameter stenosis on ICA was used as the reference standard. RESULTS: Obstructive CAD was diagnosed in 44.9% of patients (1100/2452). The median Agatston score was 74. Diagnostic accuracy of CTA for the detection of obstructive CAD (81.1%, 95% confidence interval [CI]: 77.5 to 84.1%) was significantly higher than that of the Agatston score (68.8%, 95% CI: 64.2 to 73.1%, p < 0.001). Among patients with an Agatston score of zero, 17% (101/600) had obstructive CAD. Diagnostic accuracy of CTA was not significantly different in patients with low to intermediate (1 to < 100, 100-400) versus moderate to high Agatston scores (401-1000, > 1000). CONCLUSIONS: Results in our international cohort show CTA to have significantly higher diagnostic accuracy than the Agatston score in patients with stable chest pain, suspected CAD, and a clinical indication for ICA. Diagnostic performance of CTA is not affected by a higher Agatston score while an Agatston score of zero does not reliably exclude obstructive CAD. KEY POINTS: • CTA showed significantly higher diagnostic accuracy (81.1%, 95% confidence interval [CI]: 77.5 to 84.1%) for diagnosis of coronary artery disease when compared to the Agatston score (68.8%, 95% CI: 64.2 to 73.1%, p < 0.001). • Diagnostic performance of CTA was not affected by increased amount of calcium and was not significantly different in patients with low to intermediate (1 to <100, 100-400) versus moderate to high Agatston scores (401-1000, > 1000). • Seventeen percent of patients with an Agatston score of zero showed obstructive coronary artery disease by invasive angiography showing absence of coronary artery calcium cannot reliably exclude coronary artery disease.

How to keep the cath-lab of a COVID-free hub center during the pandemic in a hub and spoke cardiology network: a single center's experience.

BACKGROUND: Northern Italy has been one of the most affected area in the world by the novel severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2). The healthcare system has been overwhelmed by the huge number of patients in need of mechanical ventilation or intensive care, resulting in a delay of treatment of patients with acute coronary syndrome (ACS), due to a crash in STEMI networks and closure of a certain number of hub centers, and to a delay in patients' seeking for medical evaluation for chest pain or angina-equivalent symptoms. METHODS: In the Trentino region, a mountainous area with about 500,000 inhabitants, very close to Lombardy that was the epicenter of the pandemic in Italy, to avoid these dramatic consequences, we developed a new protocol tailored to our specificity to keep our institution, and above all the cath-lab, clean from the SARS-CoV-2 infection, to ensure full operativity for cardiologic emergencies. RESULTS: Applying this protocol during the two months of the peak of the infection in Italy no one of the staff members of the cath-lab, the ICCU or the cardiology ward tested positive to nasal swab for SARS-CoV-2 and the same result was obtained for all the patients admitted to our units. CONCLUSIONS: Our real-world experience shows that during the COVID-19 pandemic, quick activation of an appropriate protocol defining specific pathways for patients with a medical urgency is effective in minimizing healthcare personnel exposure and to preserve full operativity of the hub centers. This issue will be of a crucial importance, now that we are facing the second wave of the pandemic.

Cardiac arrest complicating cardiogenic shock: from pathophysiological insights to Impella-assisted cardiopulmonary resuscitation in a pheochromocytoma-induced Takotsubo cardiomyopathy-a case report.

BACKGROUND: A 'catecholamine storm' in a case of pheochromocytoma can lead to a transient left ventricular dysfunction similar to Takotsubo cardiomyopathy. A cardiogenic shock can thus develop, with high left ventricular end-diastolic pressure and a reduction in coronary perfusion pressure. This scenario can ultimately lead to a cardiac arrest, in which unloading the left ventricle with a peripheral left ventricular assist device (Impella®) could help in achieving the return of spontaneous circulation (ROSC). CASE SUMMARY: A patient affected by Takotsubo cardiomyopathy caused by a pheochromocytoma presented with cardiogenic shock that finally evolved into refractory cardiac arrest. Cardiopulmonary resuscitation was performed but ROSC was achieved only after Impella® placement. DISCUSSION: In the clinical scenario of Takotsubo cardiomyopathy due to pheochromocytoma, when cardiogenic shock develops treatment is difficult because exogenous catecholamines, required to maintain organ perfusion, could exacerbate hypertension and deteriorate the cardiomyopathy. Moreover, as the coronary perfusion pressure is critically reduced, refractory cardiac arrest could develop. Although veno-arterial extra-corporeal membrane oxygenation (va-ECMO) has been advocated as the treatment of choice for in-hospital refractory cardiac arrest, in the presence of left ventricular overload a device like Impella®, which carries fewer complications as compared to ECMO, could be effective in obtaining the ROSC by unloading the left ventricle.

Sex differences in clinical and angiographic characteristics in spontaneous coronary artery dissection.

Background: Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute coronary syndrome, mostly in women; however, differences between the sexes should be investigated. Materials & methods: Hundred consecutive patients affected by SCAD were identified; coronary lesions were classified according to the most recent classification and clinical and angiographic data of men and women were compared. Results: Men were significantly younger than women, with more cardiovascular risk factors. Lesions were prevalently classified as type 2A, type 2B or type 1; an angiographic pattern compatible with the presence of an intimal tear (types 1 and 1/2) was more represented in males. Conclusion: Sex-related differences in clinical and angiographic characteristics could help in shedding light on mechanisms that contribute to SCAD.

Cerebral protection in left atrial appendage closure in the presence of appendage thrombosis.

BACKGROUND: Presence of thrombus in the left atrial appendage (LAA) remains a severe contraindication to the percutaneous left atrial appendage closure procedure (LAAC), due to increased embolic risk. Recently, the experience developed in cerebral protection device in transcatheter aortic valve implantation (TAVI) procedure was translated in LAAC to address this issue. AIM: To evaluate efficacy and safety of Sentinel cerebral protection system (CPS) in supporting LAAC in real-world patient with persistent LAA thrombus. METHODS AND RESULTS: The study retrospectively enrolled consecutive patients with non-valvular atrial fibrillation (NVAF) and thrombus in LAA who underwent LAAC supported by Sentinel CPS in seven European high-volume centres. Twenty-seven patients were included with a median age of 69.1 ± 9.7 years old, with median CHA2 DS2 -VASc and HAS-BLEED scores 3 [2-5] and 3 [2.75-4], respectively. Technical and procedural success was achieved in all patients. No periprocedural TIA, stroke, or supra-aortic trunks dissection was recorded. CONCLUSIONS: In this multicenter registry, LAAC supported by Sentinel CPS in patients with LAA persistent thrombus seems to be a safe and efficacious treatment.

[Risk assessment and early predictors of survival after out-of-hospital cardiac arrest in the province of Trento, Italy]. / La valutazione del rischio e predittori precoci di sopravvivenza dopo arresto cardiaco extraospedaliero in provincia di Trento.

BACKGROUND: Early prognostication of patients experiencing out-of-hospital cardiac arrest (OHCA) remains difficult, with no recommended risk assessment tool. The aim of this study was to determine and assess the association between available variables with survival at discharge of patients with OHCA in our regional reality. METHODS: We conducted a retrospective observational study in a single-center cohort of 236 consecutive patients with OHCA and return of spontaneous circulation admitted to the S. Chiara Hospital (Trento, Italy) from 2012 to 2015. We applied a backward stepwise multivariable logistic regression performed on 26 variables significantly related to outcome to identify predictors. The final model was evaluated for discrimination with area under the curve (AUC) of a receiver operating characteristic curve and for calibration with Hosmer-Lemeshow test and with calibration belt. RESULTS: We identified four independent factors predictive of outcome: age, arterial blood pH, coronary angiography execution and intervention of helicopter. The final model presented good discrimination with an average AUC of 0.78 (95% confidence interval 0.72-0.84) and was well calibrated, as confirmed by the Hosmer-Lemeshow test (p=0.45) and the calibration belt plot (p=0.597). CONCLUSIONS: Age, arterial blood pH, coronary angiography execution and intervention of helicopter were variables predictive of outcome. Identified predictors are in agreement with the literature and relate to local reality. Accurate prognostic assessment would facilitate an earlier identification of patients who may benefit from intensive advanced post-resuscitation care.

Diagnosis of obstructive coronary artery disease using computed tomography angiography in patients with stable chest pain depending on clinical probability and in clinically important subgroups: meta-analysis of individual patient data.

OBJECTIVE: To determine whether coronary computed tomography angiography (CTA) should be performed in patients with any clinical probability of coronary artery disease (CAD), and whether the diagnostic performance differs between subgroups of patients. DESIGN: Prospectively designed meta-analysis of individual patient data from prospective diagnostic accuracy studies. DATA SOURCES: Medline, Embase, and Web of Science for published studies. Unpublished studies were identified via direct contact with participating investigators. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Prospective diagnostic accuracy studies that compared coronary CTA with coronary angiography as the reference standard, using at least a 50% diameter reduction as a cutoff value for obstructive CAD. All patients needed to have a clinical indication for coronary angiography due to suspected CAD, and both tests had to be performed in all patients. Results had to be provided using 2×2 or 3×2 cross tabulations for the comparison of CTA with coronary angiography. Primary outcomes were the positive and negative predictive values of CTA as a function of clinical pretest probability of obstructive CAD, analysed by a generalised linear mixed model; calculations were performed including and excluding non-diagnostic CTA results. The no-treat/treat threshold model was used to determine the range of appropriate pretest probabilities for CTA. The threshold model was based on obtained post-test probabilities of less than 15% in case of negative CTA and above 50% in case of positive CTA. Sex, angina pectoris type, age, and number of computed tomography detector rows were used as clinical variables to analyse the diagnostic performance in relevant subgroups. RESULTS: Individual patient data from 5332 patients from 65 prospective diagnostic accuracy studies were retrieved. For a pretest probability range of 7-67%, the treat threshold of more than 50% and the no-treat threshold of less than 15% post-test probability were obtained using CTA. At a pretest probability of 7%, the positive predictive value of CTA was 50.9% (95% confidence interval 43.3% to 57.7%) and the negative predictive value of CTA was 97.8% (96.4% to 98.7%); corresponding values at a pretest probability of 67% were 82.7% (78.3% to 86.2%) and 85.0% (80.2% to 88.9%), respectively. The overall sensitivity of CTA was 95.2% (92.6% to 96.9%) and the specificity was 79.2% (74.9% to 82.9%). CTA using more than 64 detector rows was associated with a higher empirical sensitivity than CTA using up to 64 rows (93.4% v 86.5%, P=0.002) and specificity (84.4% v 72.6%, P<0.001). The area under the receiver-operating-characteristic curve for CTA was 0.897 (0.889 to 0.906), and the diagnostic performance of CTA was slightly lower in women than in with men (area under the curve 0.874 (0.858 to 0.890) v 0.907 (0.897 to 0.916), P<0.001). The diagnostic performance of CTA was slightly lower in patients older than 75 (0.864 (0.834 to 0.894), P=0.018 v all other age groups) and was not significantly influenced by angina pectoris type (typical angina 0.895 (0.873 to 0.917), atypical angina 0.898 (0.884 to 0.913), non-anginal chest pain 0.884 (0.870 to 0.899), other chest discomfort 0.915 (0.897 to 0.934)). CONCLUSIONS: In a no-treat/treat threshold model, the diagnosis of obstructive CAD using coronary CTA in patients with stable chest pain was most accurate when the clinical pretest probability was between 7% and 67%. Performance of CTA was not influenced by the angina pectoris type and was slightly higher in men and lower in older patients. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42012002780.

Individual patient data meta-analysis for the clinical assessment of coronary computed tomography angiography: protocol of the Collaborative Meta-Analysis of Cardiac CT (CoMe-CCT).

BACKGROUND: Coronary computed tomography angiography has become the foremost noninvasive imaging modality of the coronary arteries and is used as an alternative to the reference standard, conventional coronary angiography, for direct visualization and detection of coronary artery stenoses in patients with suspected coronary artery disease. Nevertheless, there is considerable debate regarding the optimal target population to maximize clinical performance and patient benefit. The most obvious indication for noninvasive coronary computed tomography angiography in patients with suspected coronary artery disease would be to reliably exclude significant stenosis and, thus, avoid unnecessary invasive conventional coronary angiography. To do this, a test should have, at clinically appropriate pretest likelihoods, minimal false-negative outcomes resulting in a high negative predictive value. However, little is known about the influence of patient characteristics on the clinical predictive values of coronary computed tomography angiography. Previous regular systematic reviews and meta-analyses had to rely on limited summary patient cohort data offered by primary studies. Performing an individual patient data meta-analysis will enable a much more detailed and powerful analysis and thus increase representativeness and generalizability of the results. The individual patient data meta-analysis is registered with the PROSPERO database (CoMe-CCT, CRD42012002780). METHODS/DESIGN: The analysis will include individual patient data from published and unpublished prospective diagnostic accuracy studies comparing coronary computed tomography angiography with conventional coronary angiography. These studies will be identified performing a systematic search in several electronic databases. Corresponding authors will be contacted and asked to provide obligatory and additional data. Risk factors, previous test results and symptoms of individual patients will be used to estimate the pretest likelihood of coronary artery disease. A bivariate random-effects model will be used to calculate pooled mean negative and positive predictive values as well as sensitivity and specificity. The primary outcome of interest will be positive and negative predictive values of coronary computed tomography angiography for the presence of coronary artery disease as a function of pretest likelihood of coronary artery disease, analyzed by meta-regression. As a secondary endpoint, factors that may influence the diagnostic performance and clinical value of computed tomography, such as heart rate and body mass index of patients, number of detector rows, and administration of beta blockade and nitroglycerin, will be investigated by integrating them as further covariates into the bivariate random-effects model. DISCUSSION: This collaborative individual patient data meta-analysis should provide answers to the pivotal question of which patients benefit most from noninvasive coronary computed tomography angiography and thus help to adequately select the right patients for this test.

Noninvasive detection of coronary artery stenosis with 16-slice spiral computed tomography in a population at low to moderate risk for coronary artery disease.

OBJECTIVE: To evaluate the feasibility and accuracy of 16-slice spiral computed tomography (MSCT) in detecting coronary artery lesions in a low to moderate risk population. METHODS: MSCT was performed in 33/78 patients at low to moderate risk for coronary artery disease affected by mitral and/or aortic valve disease and scheduled for conventional coronary angiography for pre-surgery evaluation. The sensitivity (SE), specificity (SP), positive (PPV) and negative predictive values (NPV) to identify >or=50% obstructed lesions were evaluated. Moreover, a discriminant predictive statistical analysis was performed. RESULTS: MSCT visualised 428/479 (89%) segments identified at coronary angiography and the percentage of evaluable segments was 87%. By including all coronary branches, SE, SP, PPV and NPV were 69%, 96%, 58% and 97%, respectively. By excluding the segments with a diameter of

The role of angiotensin-converting enzyme polymorphism in congestive heart failure.

Angiotensin-converting enzyme (ACE) is a zinc metallopeptidase, with primary known functions of converting angiotensin I into the vasoactive and aldosterone-stimulating peptide angiotensin II and inactivating bradykinin. There is high variability among individuals in ACE concentrations, mainly due to the presence of a genetic polymorphism. The ACE gene has, in fact, insertion/deletion polymorphism in intron 16, consisting of a 287-base pair Alu repeat sequence, with three genotypes: insertion polymorphism, insertion/deletion polymorphism, and deletion polymorphism. The genetic effect accounts for 47% of the total variance of serum ACE. The determination of this polymorphism has allowed researchers to study the implications of the ACE gene in many case-control studies of cardiovascular disease, including myocardial infarction and hypertrophic and dilated cardiomyopathy. We review the current knowledge about the ACE gene polymorphism and its implications in heart failure secondary to ischemic or idiopathic dilated cardiomyopathy. Interpretation of the results of studies about the role of this polymorphism are controversial. The repetition of epidemio-genetic studies and the creation of adequate experimental studies will help to definitively establish the pathogenetic role of the permanent increase in ACE expression associated with the deletion polymorphism genotype.