Evaluation of hemodialysis vascular access. Perspective from Mexico.

Chronic kidney disease (CKD) has become a global health problem. In 2019, it was related to 2.53% of general global mortality (2.35-2.66%); in the same year, in Latin America, mortality related to CKD reached 5.25% (4.92-5.49%), with an annual increase of 3.37%, proving increased mortality of 102% between 1990 and 2017. A nephrology specialty in Mexico recently fulfilled its first 50 years. Despite being relatively young, nephrologists are interested in "new" sub-specialties of nephrology and learning novel techniques and problem-solving skills. Our group is the first in our country to focus solely and exclusively on comprehensive VA care and we want to position ourselves as the first Mexican interdisciplinary group focused on vascular access (GIMEXAV).

Intracoronary tenecteplase versus abciximab as adjunctive treatment during primary percutaneous coronary intervention in patients with anterior myocardial infarction.

AIMS: We sought to compare the effects of intracoronary administration of a fibrinolytic drug (tenecteplase) to those of a glycoprotein IIb/IIIa inhibitor (abciximab) in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). METHODS AND RESULTS: In this pilot trial, 76 patients (59 male) with anterior STEMI were randomised to intracoronary infusion of reduced-dose tenecteplase or abciximab during PPCI. Angiography was repeated at 48 hours to assess corrected TIMI frame count (cTFC) and TIMI myocardial perfusion grade (TMPG). The primary endpoint was infarct size as assessed by cardiac MRI. The abciximab group showed lower cTFC (median 14.1 [IQR 9.4-17.1]) than the tenecteplase group (18.2 [10.0-28.2]) (p=0.02), and the proportion of patients with TMPG grade 2/3 was higher in the abciximab group (90.3% vs. 67.7%; p=0.03). Major cardiac and cerebrovascular event rates did not differ; however, notably, 2/38 patients in the tenecteplase group experienced subacute stent thrombosis. At four months, there were no significant differences in infarct size between the tenecteplase and abciximab groups (17.0 g [9.6-27.5] vs. 21.1 g [11.3-35.0], p=0.33). CONCLUSIONS: Intracoronary administration of tenecteplase did not reduce infarct size compared to abciximab in STEMI patients undergoing PPCI. Tenecteplase exhibited poorer myocardial reperfusion and might be associated with increased subacute stent thrombosis.

Value of the coronary artery disease consortium rule in patients with acute chest pain and negative troponins referred for exercise stress testing.

OBJECTIVE: To assess the value of the pretest probability (PTP) of coronary artery disease (CAD) for predicting stress testing results and coronary events in patients with acute chest pain and negative troponins. PATIENTS AND METHODS: A total of 3527 patients without a history of CAD referred to our chest pain unit with suspected acute coronary syndromes, nondiagnostic ECGs, and negative troponin levels underwent exercise stress testing. PTP was estimated with the CAD consortium prediction rule, and was categorized as low (<15%), low-intermediate (15-65%), intermediate-high (66-85%), and high (>85%). The endpoints were the presence of signs of inducible myocardial ischemia on stress testing and the occurrence of coronary events within 6 months. RESULTS: The probability of exercise-induced myocardial ischemia was 2.6, 12.6, 42.9, and 82.1% in patients with low, low-intermediate, intermediate-high, and high PTP, respectively (Ptrend<0.001). The cumulative rate of coronary events within 6 months was also significantly lower in patients with low PTP of CAD (0.8%) than in those with low-intermediate (6.9%), intermediate-high (32.5%), or high PTP (66.7%) (Ptrend<0.001). Per 10% increment in PTP of CAD, the adjusted odds ratios for inducible myocardial ischemia and coronary events within 6 months were, respectively, 1.71 (95% confidence interval: 1.61-1.85) and 1.87 (95% confidence interval: 1.74-2.01). CONCLUSION: PTP was associated strongly with the likelihood of exercise-induced myocardial ischemia and coronary events in patients with suspected acute coronary syndromes and negative troponins. The yield of stress testing in the subset of patients with low PTP was very low.

Prognostic implication of early ventricular fibrillation among patients with ST elevation myocardial infarction.

OBJECTIVE: The aim of this study was to analyze the prognosis of patients presenting early ventricular fibrillation (VF) in the setting of ST elevation myocardial infarction (STEMI). PATIENTS AND METHODS: Among patients included in the ARIAM (Análisis del Retraso en el Infarto Agudo de Miocardio) registry with the diagnosis of STEMI, those who received primary revascularization and were admitted in the first 12 h were analyzed retrospectively. RESULTS: From January 2007 to January 2012, 8340 patients were included in the STEMI cohort and 680 (8.2%) of them presented with VF before admission to the ICU (VF). This group comprised younger patients with fewer comorbidities. They received more often primary angioplasty (33.7 vs. 24.9%; P<0.001), had more prevalence of Killip class greater than or equal to 2 at admission (37.5 vs. 17.8%; P<0.001), and suffered more often cardiogenic shock (18.5 vs. 5.9%, P<0.001). By logistic regression analysis, VF was associated with a greater in-hospital mortality [odds rate (OR): 2.08, 95% confidence interval (CI): 1.57-2.81, P<0.001]. After a propensity score matching process, VF was associated with in-hospital mortality (OR: 1.53, 95% CI: 1.05-2.25, P=0.028). However, when analyzing patients treated by primary angioplasty, the mortality was not significantly related to VF (OR: 0.86, 95% CI: 0.45-1.61, P=0.628). CONCLUSION: Our results show that VF before ICU admission was an independent predictor of in-hospital outcome in a cohort of patients in whom fibrinolysis was the most used revascularization therapy. However, this prognostic value was not found in patients treated with primary angioplasty.

A clinical score to obviate the need for cardiac stress testing in patients with acute chest pain and negative troponins.

INTRODUCTION: Although cardiac stress testing may help establish the safety of early discharge in patients with suspected acute coronary syndromes and negative troponins, more cost-effective strategies are necessary. We aimed to develop a clinical prediction rule to safely obviate the need for cardiac stress testing in this setting. METHODS: A decision rule was derived in a prospective cohort of 3001 patients with acute chest pain and negative troponins, and validated in a set of 1473 subjects. The primary end point was a composite of positive cardiac stress testing (in the absence of a subsequent negative coronary angiogram), positive coronary angiography, or any major coronary events within 3 months. RESULTS: A score chart was built based on 7 variables: male sex (+2), age (+1 per decade from the fifth decade), diabetes mellitus (+2), hypercholesterolemia (+1), prior coronary revascularization (+2), type of chest pain (typical angina, +5; non-specific chest pain, -3), and non-diagnostic repolarization abnormalities (+2). In the validation set, the model showed good discrimination (c statistic = 0.84; 95% confidence interval, 0.82-0.87) and calibration (Hosmer-Lemeshow goodness-of-fit test, P= .34). If stress tests were avoided in patients in the validation sample with a sum score of 0 or lower, the number of referrals would be reduced by 23.4%, yielding a negative predictive value of 98.8% (95% confidence interval, 97.0%-99.7%). CONCLUSION: This novel prediction rule based on a combination of readily available clinical characteristics may be a valuable tool to decide whether stress testing can be reliably avoided in patients with acute chest pain and negative troponins.

Troponin levels within the normal range and probability of inducible myocardial ischemia and coronary events in patients with acute chest pain.

BACKGROUND/OBJECTIVES: Patients with suspected acute coronary syndromes and negative cardiac troponin (cTn) levels are deemed at low risk. Our aim was to assess the effect of cTn levels on the frequency of inducible myocardial ischemia and subsequent coronary events in patients with acute chest pain and cTn levels within the normal range. METHODS: We evaluated 4474 patients with suspected acute coronary syndromes, nondiagnostic electrocardiograms and serial cTnI levels below the diagnostic threshold for myocardial necrosis using a conventional or a sensitive cTnI assay. The end points were the probability of inducible myocardial ischemia and coronary events (i.e., coronary death, myocardial infarction or coronary revascularization within 3 months). RESULTS: The probability of inducible myocardial ischemia was significantly higher in patients with detectable peak cTnI levels (25%) than in those with undetectable concentrations (14.6%, p<0.001). These results were consistent regardless of the type of cTnI assay, the type of stress testing modality, or the timing for cTnI measurement, and remained significant after multivariate adjustment (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.21-1.79, p<0.001). The rate of coronary events at 3 months was also significantly higher in patients with detectable cTnI levels (adjusted OR 2.08, 95% CI 1.64-2.64, p<0.001). CONCLUSIONS: Higher cTnI levels within the normal range were associated with a significantly increased probability of inducible myocardial ischemia and coronary events in patients with suspected acute coronary syndromes and seemingly negative cTnI.

Incremental value of exercise echocardiography over exercise electrocardiography in a chest pain unit.

BACKGROUND: Limited data are available on the added value of exercise echocardiography (ExEcho) over exercise electrocardiography (ExECG) in patients with suspected acute coronary syndromes (ACS) referred to a chest pain unit. We aimed to assess the incremental value of ExEcho over ExECG in this setting. METHODS: ExECG and ExEcho were performed in parallel in 1052 patients with suspected ACS, nondiagnostic but interpretable electrocardiograms, and negative serial troponin results. The primary outcome was a composite of coronary death, nonfatal myocardial infarction or unstable angina with angiographic documentation of significant coronary artery disease within 6 months. RESULTS: The primary outcome occurred in 2/614 patients (0.3%) with both negative ExECG and ExEcho, 3/60 (5%) with positive ExECG and negative ExEcho, 73/135 (54.1%) with negative ExECG and positive ExEcho, 106/136 (77.9%) with both positive ExECG and ExEcho, and 8/107 (7.5%) with inconclusive results. The addition of ExEcho data to a model based on clinical and ExECG data significantly increased the c statistic from 0.898 to 0.968 (change +0.070, 95% confidence interval 0.052-0.092), with a continuous net reclassification improvement of 1.56 and an integrated discrimination improvement of 22% (p<0.001). Decision curve analysis showed that a strategy of referral to coronary angiography based on ExEcho was associated with the highest net benefit and with the largest reduction in unnecessary coronary angiographies. CONCLUSION: ExEcho provides significant incremental prognostic information and higher net clinical benefit than a strategy based on ExECG in patients referred to a chest pain unit for suspected ACS and negative troponin levels.

Efecto a largo plazo de los estanoles vegetales en el perfil lipídico de pacientes con hipercolesterolemia. Ensayo clínico aleatorizado / Long-term effects of plant stanols on the lipid profile of patients with hypercholesterolemia. A randomized clinical trial

Introducción y objetivos. El consumo de estanoles vegetales puede contribuir a un mejor control a largo plazo del colesterol. El objetivo es evaluar la eficacia del aporte de estanoles vegetales, a dosis de 2 g/día, en la reducción de las cifras de colesterol unido a lipoproteínas de baja densidad de los pacientes con hipercolesterolemia. Métodos. Se realizó un ensayo clínico aleatorizado, a doble ciego y controlado con placebo, en el que se incluyó a 182 sujetos adultos diagnosticados de hipercolesterolemia. Se administró yogur líquido con 2 g de estanoles vegetales a 91 sujetos del grupo intervención y yogur no suplementado a 91 del grupo control. La variable principal fue la variación del perfil lipídico a los 12 meses. Resultados. En comparación con el placebo, a los 12 meses se observó una disminución significativamente superior del colesterol unido a lipoproteínas de baja densidad en el grupo que tomó estanoles: 13,7 (intervalo de confianza del 95%, 3,2-24,1) mg/dl (p = 0,011). En este grupo fue significativamente superior la proporción de sujetos que redujeron en más del 10% sus cifras de colesterol unido a lipoproteínas de baja densidad (riesgo relativo = 1,7; intervalo confianza del 95%, 1,1-2,7). En el grupo tratado, el colesterol unido a lipoproteínas de baja densidad descendió, en promedio, un 11,0 ± 23,9%. Conclusiones. Los resultados confirman que la administración de estanoles vegetales en dosis de 2 g/día durante 1 año produce una reducción significativa (ligeramente superior al 10%) de las concentraciones de colesterol unido a lipoproteínas de baja densidad en sujetos con hipercolesterolemia (AU)

Introduction and objectives. Plant stanol consumption may improve long-term cholesterol control. The aim of the present study was to evaluate the effectiveness of 2 g/day of plant stanols in reducing low-density lipoprotein cholesterol levels in patients with hypercholesterolemia. Methods. This randomized, double-blind, and placebo-controlled study included 182 adults diagnosed with hypercholesterolemia. A yogurt drink containing 2 g of plant stanols was administered to 91 participants in the intervention group; 91 participants in the control group received unsupplemented yogurt. The primary end point was the change in the lipid profile at 12 months. Results. Low-density lipoprotein cholesterol levels at 12 months were significantly more reduced in the stanol intervention group than in the control group: 13.7 (95% confidence interval, 3.2-24.1) mg/dL (P = .011). A reduction of more than 10% in low-density lipoprotein cholesterol was achieved by a significantly higher proportion of participants in the intervention group (relative risk = 1.7; 95% confidence interval, 1.1-2.7). In this group, the mean (standard deviation) level of low-density lipoprotein cholesterol decreased by 11.0% (23.9%). Conclusions. Our results confirm that administration of plant stanols at a dosage of 2 g/day for 12 months significantly reduces (by slightly more than 10%) the concentrations of low-density lipoprotein cholesterol in individuals with hypercholesterolemia (AU)

Temporal changes in the use and results of exercise echocardiography.

AIMS: Limited data are available regarding changes over time in referral patterns and outcomes of non-invasive cardiac stress testing. Our aim was to evaluate the temporal changes in the use and results of exercise echocardiography in our area of reference. METHODS AND RESULTS: A total of 12 339 patients referred to our unit for exercise echocardiography between 1997 and 2012 were included. We divided the 16-year period into four quadrennia and evaluated the changes in clinical data, results of the tests, referrals for invasive management and outcomes. We observed a gradual decrease in the frequency of detection of myocardial ischaemia from 35.3% in1997-2000 to 25.4% in 2009-12 (P < 0.001). There was also a progressive increase in the prevalence of cardiovascular risk factors and in the frequency of non-ischaemic chest pain and dyspnoea, while the proportion of patients with prior myocardial infarction and non-interpretable electrocardiograms declined. The rate of referral to coronary angiography within 6 months decreased from 24.8% in 1997-2000 to 19.6% in 2009-12 (P < 0.001), but the rate of coronary revascularization remained almost unchanged (13.1 to 11.7%, P for the trend = 0.16). We also observed a progressive decrease in the 1-year mortality rate from 3.4 to 1% (P < 0.001). CONCLUSION: Over a 16-year period, there was a gradual decrease in the frequency of myocardial ischaemia among patients referred to our unit for exercise echocardiography, which was parallel to changes in their clinical profile. However, this was not accompanied by a significant reduction in the rate of coronary revascularization.

Prognostic impact of clopidogrel pretreatment in patients with acute coronary syndrome managed invasively.

Pretreatment with antiP2Y12 agents before angiography in acute coronary syndrome (ACS) is associated with a reduction in thrombotic events. However, recent evidences have questioned the benefits of upstream antiP2Y12, reporting a higher incidence of bleeding. We analyzed the prognostic impact of clopidogrel pretreatment in a large cohort of invasively managed patients with ACS. In hospital, safety and efficacy of clopidogrel pretreatment were retrospectively analyzed in patients included in the ARIAM-Andalucía Registry (Analysis of Delay in Acute Myocardial Infarction). Propensity score and inverse probability of treatment weighting analysis were performed to control treatment selection bias. Results were stratified by ACS type. Sensitivity analyses were used to explore stability of the overall treatment effect. Of 9,621 patients managed invasively, 69% received clopidogrel before coronary angiography. In the ST-elevation myocardial infarction group, pretreatment was associated with a significant reduction in reinfarction (odds ratio 0.53, 95% confidence interval [CI] 0.27 to 0.96; p = 0.027), stent thrombosis (odds ratio 0.15, 95% CI 0.06 to 0.38; p <0.0001), and mortality (odds ratio 0.67, 95% CI 0.48 to 0.94; p = 0.020), with an increase in minor bleeding but remained as a net clinical benefit strategy. Those benefits were not present in patients without ST elevation (non-ST elevation ACS). The weighting and propensity analysis confirmed the same results. An interaction between pretreatment duration and bleeding was observed. In conclusion, pretreatment with clopidogrel reduced the occurrence of death and thrombotic outcomes at the cost of minor bleeding. Those benefits exclusively affected ST-elevation myocardial infarction cases. The potential benefit of routine upstream pretreatment in patients with non-ST-elevation ACS should be reappraised at the present.

Long-term Effects of Plant Stanols on the Lipid Profile of Patients With Hypercholesterolemia. A Randomized Clinical Trial.

INTRODUCTION AND OBJECTIVES: Plant stanol consumption may improve long-term cholesterol control. The aim of the present study was to evaluate the effectiveness of 2g/day of plant stanols in reducing low-density lipoprotein cholesterol levels in patients with hypercholesterolemia. METHODS: This randomized, double-blind, and placebo-controlled study included 182 adults diagnosed with hypercholesterolemia. A yogurt drink containing 2g of plant stanols was administered to 91 participants in the intervention group; 91 participants in the control group received unsupplemented yogurt. The primary end point was the change in the lipid profile at 12 months. RESULTS: Low-density lipoprotein cholesterol levels at 12 months were significantly more reduced in the stanol intervention group than in the control group: 13.7 (95% confidence interval, 3.2-24.1) mg/dL (P=.011). A reduction of more than 10% in low-density lipoprotein cholesterol was achieved by a significantly higher proportion of participants in the intervention group (relative risk=1.7; 95% confidence interval, 1.1-2.7). In this group, the mean (standard deviation) level of low-density lipoprotein cholesterol decreased by 11.0% (23.9%). CONCLUSIONS: Our results confirm that administration of plant stanols at a dosage of 2 g/day for 12 months significantly reduces (by slightly more than 10%) the concentrations of low-density lipoprotein cholesterol in individuals with hypercholesterolemia. Trial registration (www.ClinicalTrials.gov): Current Controlled Trials NCT01406106.

Torsión ventricular izquierda durante el ejercicio en pacientes con y sin respuesta isquémica a la ecocardiografía de ejercicio / Left Ventricular Torsion During Exercise in Patients With and Without Ischemic Response to Exercise Echocardiography

Introducción y objetivos La torsión ventricular izquierda disminuye durante la isquemia miocárdica transmural, pero el efecto del ejercicio en aquella no se ha estudiado de manera detallada. Nuestra hipótesis era que la isquemia inducida por el ejercicio puede deteriorar la torsión ventricular izquierda. Por consiguiente, nuestro objetivo fue estudiar los efectos del ejercicio en la torsión ventricular izquierda en pacientes con una respuesta normal a la ecocardiografía de ejercicio y en pacientes con una respuesta normal. Métodos Se llevó a cabo un análisis retrospectivo de 172 pacientes con fracción de eyección Métodos: Se llevó a cabo un análisis retrospectivo de 172 pacientes con fracción de eyección ≥ 50% remitidos a ecocardiografía de ejercicio, a los que se examinó mediante speckle tracking en reposo, en ejercicio máximo y después del ejercicio. La torsión se definió como rotación apical - rotación basal (en grados) / longitud del ventrículo izquierdo (en centímetros). Un total de 114 pacientes presentaron una ecocardiografía de esfuerzo normal y 58 mostraron respuesta isquémica a la ecocardiografía de ejercicio. RESULTADOS: Los pacientes con respuesta isquémica a la prueba presentaron menor rotación basal en el ejercicio máximo (+0,30 ± 2,39° frente a -0,65 ± 2,61° en el grupo de respuesta normal; p = 0,03), mientras que la rotación máxima apical fue similar (respuesta isquémica a la prueba, 7,80 ± 3,51°; respuesta normal, 7,27 ± 3,28°; p = 0,36). La torsión en el ejercicio máximo fue también similar (1,07 ± 0,60° en el grupo de respuesta isquémica frente a 1,16 ± 0,57° en el grupo de respuesta normal; p = 0,37). Se observó mayor deterioro de la rotación basal máxima en los pacientes con afección anterior o anterior + posterior (respuesta isquémica anterior, +1,22 ± 2,45°; respuesta isquémica anterior + posterior, -0,20 ± 2,25°; respuesta isquémica posterior, -0,71 ± 1,96°; respuesta normal, -0,65 ± 2,60°; p = 0,02). CONCLUSIONES: La rotación basal en el ejercicio máximo está deteriorada en los pacientes con respuesta isquémica a la ecocardiografía de ejercicio, en especial la de quienes presentan afección anterior. La rotación apical y la torsión son similares a las de los pacientes con una ecocardiografía de ejercicio normal

Introduction and objectives Left ventricular torsion decreases during transmural myocardial ischemia, but the effect of exercise on left ventricular torsion has not been widely studied. We hypothesized that exercise-induced ischemia may impair left ventricular torsion. Therefore, our aim was to study the effects of exercise on left ventricular torsion in patients with an ischemic response to exercise echocardiography and in patients with a normal response. Methods A retrospective analysis was performed in 172 patients with ejection fraction patients with ejection fraction ≥ 50% who were referred for exercise-echocardiography and studied by speckle imaging at rest, peak and postexercise. Torsion was defined as apical rotation - basal rotation (in degrees) / left ventricular length (in centimeters). A total of 114 patients had a normal exercise echocardiography and 58 patients had an ischemic response to exercise echocardiography. Results: Patients with ischemic response to the test exhibited less basal rotation at peak exercise (+0.30° [2.39°] vs –0.65° [2.61°] in the normal group; P = .03), whereas peak apical rotation was similar (ischemic response to the test, 7.80° [3.51°]; normal response, 7.27° [3.28°]; P =.36). Torsion at peak exercise was also similar (1.07° [0.60°] in the ischemic response to the test group vs 1.16° [0.57°] in normal group; P =.37). A more impaired peak basal rotation was found in patients with anterior or anterior+posterior involvement (anterior ischemic response, +1.22° [2.45°]; anterior + posterior ischemic response, –0.20° [2.25°]; posterior ischemic response, –0.71° [1.96°]; normal response, –0.65° [2.60°]; P =.02). Conclusions: Basal rotation at peak exercise is impaired in patients with an ischemic response to exercise echocardiography, particularly in those with anterior involvement. Apical rotation and torsion are similar to those in patients with normal exercise echocardiography

Left ventricular torsion during exercise in patients with and without ischemic response to exercise echocardiography.

INTRODUCTION AND OBJECTIVES: Left ventricular torsion decreases during transmural myocardial ischemia, but the effect of exercise on left ventricular torsion has not been widely studied. We hypothesized that exercise-induced ischemia may impair left ventricular torsion. Therefore, our aim was to study the effects of exercise on left ventricular torsion in patients with an ischemic response to exercise echocardiography and in patients with a normal response. METHODS: A retrospective analysis was performed in 172 patients with ejection fraction ≥ 50% who were referred for exercise-echocardiography and studied by speckle imaging at rest, peak and postexercise. Torsion was defined as apical rotation - basal rotation (in degrees) / left ventricular length (in centimeters). A total of 114 patients had a normal exercise echocardiography and 58 patients had an ischemic response to exercise echocardiography. RESULTS: Patients with ischemic response to the test exhibited less basal rotation at peak exercise (+0.30° [2.39°] vs -0.65° [2.61°] in the normal group; P = .03), whereas peak apical rotation was similar (ischemic response to the test, 7.80° [3.51°]; normal response, 7.27° [3.28°]; P =.36). Torsion at peak exercise was also similar (1.07° [0.60°] in the ischemic response to the test group vs 1.16° [0.57°] in normal group; P =.37). A more impaired peak basal rotation was found in patients with anterior or anterior+posterior involvement (anterior ischemic response, +1.22° [2.45°]; anterior + posterior ischemic response, -0.20° [2.25°]; posterior ischemic response, -0.71° [1.96°]; normal response, -0.65° [2.60°]; P =.02). CONCLUSIONS: Basal rotation at peak exercise is impaired in patients with an ischemic response to exercise echocardiography, particularly in those with anterior involvement. Apical rotation and torsion are similar to those in patients with normal exercise echocardiography.