Deep inspiration breath-hold radiation therapy in left-sided breast cancer patients: a single-institution retrospective dosimetric analysis of organs at risk doses.

BACKGROUND: Radiotherapy can induce cardiac injury in left-sided breast cancer cases. Cardiac-sparing irradiation using the deep inspiration breath-hold (DIBH) technique can achieve substantial dose reduction to vulnerable cardiac substructures compared with free breathing (FB). This study evaluated the dosimetric differences between both techniques at a single institution. METHODS: From 2017 to 2019, 130 patients with left-sided breast cancer underwent breast-conserving surgery (BCS; n = 121, 93.1%) or mastectomy (ME; n = 9, 6.9%) along with axillary lymph node staging (n = 105, 80.8%), followed by adjuvant irradiation in DIBH technique; adjuvant systemic therapy was included if applicable. 106 (81.5%) patients received conventional and 24 (18.5%) hypofractionated irradiation. Additionally, 12 patients received regional nodal irradiation. Computed tomography (CT) scans in FB and DIBH position were performed for all patients. Intrafractional 3D position monitoring of the patient surface in deep inspiration and breath gating was performed using Sentinel and Catalyst HD 3D surface scanning systems (C-RAD, Catalyst, C­RAD AB, Uppsala, Sweden). Individual coaching and determination of breathing amplitude during the radiation planning CT was performed. Three-dimensional treatment planning was performed using standard tangential treatment portals (6 or 18 MV). The delineation of cardiac structures and both lungs was done in both the FB and the DIBH scan. RESULTS: All dosimetric parameters for cardiac structures were significantly reduced (p < 0.01 for all). The mean heart dose (Dmean) in the DIBH group was 1.3 Gy (range 0.5-3.6) vs. 2.2 Gy (range 0.9-8.8) in the FB group (p < 0.001). The Dmean for the left ventricle (LV) in DIBH was 1.5 Gy (range 0.6-4.5), as compared to 2.8 Gy (1.1-9.5) with FB (p < 0.001). The parameters for LV (V10 Gy, V15 Gy, V20 Gy, V23 Gy, V25 Gy, V30 Gy) were reduced by about 100% (p < 0.001). The LAD Dmean in the DIBH group was 4.1 Gy (range 1.2-33.3) and 14.3 Gy (range 2.4-37.5) in the FB group (p < 0.001). The median values for LAD such as V15 Gy, V20 Gy, V25 Gy, V30 Gy, and V40 Gy decreased by roughly 100% (p < 0.001). An increasing volume of left lung in the DIBH position resulted in dose sparing of cardiac structures. CONCLUSION: For all ascertained dosimetric parameters, a significant dose reduction could be achieved in DIBH technique.

A planning strategy may reduce the risk of heart diseases and radiation pneumonia: Avoiding the specific heart substructures.

BACKGROUND: Dose to heart substructures is a better predictor for major adverse cardiac events (MACE) than mean heart dose (MHD). We propose an avoidance planning strategy for important cardiac substructures. MATERIAL AND METHODS: Two plans, clinical and cardiac substructure-avoidance plan, were generated for twenty patients. Five dose-sensitive substructures, including left ventricle, pulmonary artery, left anterior descending branch, left circumflex branch and the coronary artery were chosen. The avoidance plan aims to meet the target criteria and organ-at-risk (OARs) constraints while minimizing the dose parameters of the above five substructures. The dosimetric assessments included the mean dose and the maximum dose of cardiac substructures and several volume parameters. In addition, we also evaluated the relative risk of coronary artery disease (CAD), chronic heart failure (CHF), and radiation pneumonia (RP). RESULTS: Pearson correlation coefficient and R2 value of linear regression fitting demonstrated that MHD had poor prediction ability for the mean dose of the cardiac substructures. Compared to clinical plans, an avoidance plan is able to statistically significantly decrease the dose to key substructures. Meanwhile, the dose to OARs and the coverage of the target are comparable in the two plans. In addition, it can be observed that the avoidance plan statistically decreases the relative risks of CAD, CHF, and RP. CONCLUSIONS: The substructure-avoidance planning strategy that incorporates the cardiac substructures into optimization process, can protect the important heart substructures, such as left ventricle, left anterior descending branch and pulmonary artery, achieving the substantive sparing of dose-sensitive cardiac structures, and have the potential to decrease the relative risks of CAD, CHF, and RP.

Heart toxicity from breast cancer radiotherapy : Current findings, assessment, and prevention.

BACKGROUND: Late cardiac toxicities caused by (particularly left-sided) breast radiotherapy (RT) are now recognized as rare but relevant sequelae, which has prompted research on risk structure identification and definition of threshold doses to heart subvolumes. The aim of the present review was to critically discuss the clinical evidence on late cardiac reactions based on dose-dependent outcome reports for mean heart doses as well as doses to cardiac substructures. METHODS: A literature review was performed to examine clinical evidence on radiation-induced heart toxicities. Mean heart doses and doses to cardiac substructures were focused upon based on dose-dependent outcome reports. Furthermore, an overview of radiation techniques for heart protection is given and non-radiotherapeutic aspects of cardiotoxicity in the multimodal setting of breast cancer treatment are discussed. RESULTS: Based on available findings, the DEGRO breast cancer expert panel recommends the following constraints: mean heart dose <2.5 Gy; DmeanLV (mean dose left ventricle) < 3 Gy; V5LV (volume of LV receiving ≥5 Gy) < 17%; V23LV (volume of LV receiving ≥23 Gy) < 5%; DmeanLAD (mean dose left descending artery) < 10 Gy; V30LAD (volume of LAD receiving ≥30 Gy) < 2%; V40LAD (volume of LAD receiving ≥40 Gy) < 1%. CONCLUSION: In addition to mean heart dose, breast cancer RT treatment planning should also include constraints for cardiac subvolumes such as LV and LAD. The given constraints serve as a clinicians' aid for ensuring adequate heart protection. The individual decision between sufficient protection of cardiac structures versus optimal target volume coverage remains in the physician's hand. The risk of breast cancer-specific mortality and a patient's cardiac risk factors must be individually weighed up against the risk of radiation-induced cardiotoxicity.

Effects of Radiotherapy in Coronary Artery Disease.

PURPOSE OF REVIEW: This review describes the effects of radiotherapy (RT) on coronary artery disease, its mechanisms, and clinical and laboratory evidence and discusses ways to minimize radiation-induced coronary atherosclerosis. RECENT FINDINGS: Radiation-induced cardiac toxicity is known in patients undergoing thoracic RT. One of the damages occurs in the coronary arteries, with accelerated atherosclerosis manifesting decades later. There is clinical and laboratory evidence of coronary damage in retrospective studies, systematic reviews, and meta-analyses. Clinical studies have shown that RT cardiotoxicity occurs decades after radiation, regardless of chemotherapy, and may occur earlier in patients with pre-existing risk factors or disease. The pathogenesis of radiation-induced coronary artery disease is complex and multifactorial, including endothelial dysfunction, altered vascular tone, hemostatic imbalance, and inflammatory activation. Some factors are responsible, such as mean heart dose, RT chest site, patient position, techniques, and breathing maneuvers. There are approaches to reduce radiation-induced cardiac toxicity. Among them, besides the mentioned factors, metformin and anti-inflammatory agents can minimize coronary damage, with impact on morbidity and mortality.

Efficacity of Deep Inspiration Breath Hold and Intensity-Modulated Radiotherapy in Preventing Perfusion Defect for Left Sided Breast Cancer (EDIPE): A Prospective Cohort Study Protocol.

Breast radiotherapy can lead to radiation-induced cardiac disease, particularly in left breast cancers. Recent studies have shown that subclinical cardiac lesions, such as myocardial perfusion deficits, may occur early after radiotherapy. The primary method for irradiating breast cancer, known as opposite tangential field radiotherapy, can cause the anterior interventricular coronary artery to receive a high dose of radiation during left breast irradiation. To explore alternative approaches that could reduce the risk of myocardial perfusion defects in patients with left breast cancer, we plan to conduct a prospective single-center study using a combination of deep inspiration breath hold radiotherapy and intensity modulated radiation therapy. The study will use stress and, if necessary, resting myocardial scintigraphy to assess myocardial perfusion. The trial aims to show that reducing the cardiac dose with these techniques can prevent the appearance of early (3-month) and medium-term (6- and 12-month) perfusion disorders.

Contaminant Metals and Cardiovascular Health.

A growing body of research has begun to link exposure to environmental contaminants, such as heavy metals, with a variety of negative health outcomes. In this paper, we sought to review the current research describing the impact of certain common contaminant metals on cardiovascular (CV) health. We reviewed ten metals: lead, barium, nickel, chromium, cadmium, arsenic, mercury, selenium, zinc, and copper. After a literature review, we briefly summarized the routes of environmental exposure, pathophysiological mechanisms, CV health impacts, and exposure prevention and/or mitigation strategies for each metal. The resulting article discloses a broad spectrum of pathological significance, from relatively benign substances with little to no described effects on CV health, such as chromium and selenium, to substances with a wide-ranging and relatively severe spectrum of CV pathologies, such as arsenic, cadmium, and lead. It is our hope that this article will provide clinicians with a practical overview of the impact of these common environmental contaminants on CV health as well as highlight areas that require further investigation to better understand how these metals impact the incidence and progression of CV diseases.

Dosimetric evaluation of the heart and left anterior descending artery dose in radiotherapy for Japanese patients with breast cancer.

Intensity-modulated radiotherapy (IMRT) has been used for breast cancer as well as in field-in-field techniques. Few dosimetric comparison studies have been conducted using IMRT and volumetric modulated arc therapy (VMAT) for Japanese patients. We aimed to study such patients. Thirty-two patients with left-sided breast cancer were enrolled. We conducted the following five treatment plans: two field-static IMRT (2F-S-IMRT), four field-static IMRT (4F-S-IMRT), 40° dual partial arc VMAT (40d-VMAT), 80° dual partial arc VMAT (80d-VMAT) and 210° partial VMAT (210p-VMAT). We evaluated the following: level of coverage of planning target volume (PTV) of 95% for irradiation at a dose of 50 Gy (D95) and the percentage of the heart and left anterior descending artery (LAD) volume that received 10 Gy or more (V10). As a result, the coverage of 40d-VMAT for the prescribed PTV dose of D95 was significantly lower than that of the other treatment plans (P < 0.05). Regarding heart V10 and LAD V10, 2F-S-IMRT, 40d-VMAT and 80d-VMAT showed significantly lower dose than the other treatment plans (P < 0.05). In conclusion, among the five plans, 2F-S-IMRT is recommended for Japanese patients because of high coverage of D95 of PTV, low V10 of the heart and LAD and the monitor unit value was the lowest.

Can we safely reduce the radiation dose to the heart while compromising the dose to the lungs in oesophageal cancer patients?

PURPOSE: The aim of this study was to evaluate which clinical and treatment-related factors are associated with heart and lung toxicity in oesophageal cancer patients treated with chemoradiation (CRT). The secondary objective was to analyse whether these toxicities are associated with overall survival (OS). MATERIALS AND METHODS: The study population consisted of a retrospective cohort of 216 oesophageal cancer patients treated with curative CRT. Clinical and treatment related factors were analysed for OS and new pulmonary and cardiac events by multivariable regression analyses. The effect of these toxicities on OS was assessed by Kaplan Meyer analyses. RESULTS: Multivariable analysis revealed that pulmonary toxicity was best predicted by the mean lung dose. Cardiac complications were diverse; the most frequently occurring complication was pericardial effusion. Several cardiac dose parameters correlated with this endpoint. Patients developing radiation pneumonitis had significantly worse OS than patients without radiation pneumonitis, while no difference was observed in OS between patients with and without pericardial effusion. OS was best predicted by the V45 of the lung and tumour stage. None of the cardiac dose parameters predicted OS in multivariable analyses. CONCLUSION: Cardiac dose volume parameters predicted the risk of pericardial effusion and pulmonary dose volume parameters predicted the risk of radiation pneumonitis. However, in this patient cohort, pulmonary DVH parameters (V45) were more important for OS than cardiac DVH parameters. These results suggest that reducing the cardiac dose at the expense of the dose to the lungs might not always be a good strategy in oesophageal cancer patients.

Fully automated detection of heart irradiation in cine MV images acquired during breast cancer radiotherapy.

PURPOSE: To develop robust automated detection of heart irradiation in continuous portal images (cine MV images) of tangential breast cancer treatments. METHODS: Cine MV images of 302 tangential field deliveries were recorded for ten left-sided breast cancer patients receiving deep-inspiration breath-hold radiotherapy. An algorithm for fully automated heart edge detection in cine MV images was developed and tested for all images. The algorithm first enhances the heart edge contrast greatly by exploiting that pixels on the heart edge change their intensity cyclically, and highly correlated, at 1-3 Hz due to heartbeat. The algorithm then detects the heart edge in the enhanced image and calculates the exposed heart area within the field aperture. RESULTS: The algorithm correctly identified the heart edge in all cine MV series with heart exposure (169 of 302 field deliveries). With conservative selection criteria the algorithm on average identified 70 heart edge pixels in the heart-including field deliveries (range: 10-230) without false positives. With less strict criteria 106 heart edge pixels were identified on average (range: 13-262) with 0.6% being false positives. The heart edge bordering the lung was segmented highly reliably even a few millimeters outside the field edge. For six patients with frequent heart irradiation, the exposed heart area showed large interfraction variations and smaller intrafraction variations. CONCLUSIONS: Automated heart edge detection in cine MV images was proposed, developed and shown to be highly efficient for heart exposure detection in tangential breast fields. It may allow unsupervised surveillance of heart exposure at all tangential breast cancer treatments in a clinic.

Inclusion of heart substructures in the optimization process of volumetric modulated arc therapy techniques may reduce the risk of heart disease in Hodgkin's lymphoma patients.

BACKGROUND AND PURPOSE: Radiotherapy is an effective treatment for Hodgkin's lymphoma (HL), but increases the risk of long term complications as cardiac events and second cancers. This study aimed to reduce the risk of cardiovascular events through an optimization of the dose distribution on heart substructures in mediastinal HL patients with the adoption of different volumetric modulated arc therapy (VMAT) techniques, while maintaining the same risk of second cancer induction on lungs and breasts. MATERIALS AND METHODS: Thirty patients (15 males and 15 females, 15 bulky lesions) treated between 2012 and 2017 at our institution were selected. Disease extent was mediastinum plus neck (n = 10), mediastinum plus unilateral axilla (n = 10) and mediastinum alone (n = 10). Lungs, breasts, whole heart and sub-structures (coronary arteries, valves and chambers) were contoured as organs at risk and included in the optimization process. A "first-generation" multi-arc butterfly VMAT (B-VMAT) planning solution was compared to a full-arc butterfly VMAT (FaB-VMAT) approach, consisting of a full arc plus a non-coplanar arc. Lifetime attributable risk (LAR) of second breast and lung cancer and relative risk (RR) of coronary artery disease (CAD) and chronic heart failure (CHF) were estimated. RESULTS: FaB-VMAT resulted in lower mean dose to whole heart (7.6 vs 6.9 Gy, p = 0.003), all coronary arteries (16.1 vs 13.5 Gy, p < 0.001), left ventricle (4.2 vs 3.4 Gy, p = 0.007) and in lower V20Gy to the lungs (15% vs 14%, p = 0.008). A significant lower RR for CAD and CHF was observed for FaB-VMAT. The risk of second breast and lung cancer was comparable between the two solutions, with the exception of female patients with mediastinal bulky involvement, where B-VMAT resulted in lower mean dose (2.8 vs 3.5 Gy, p = 0.03) and V4Gy (22% vs 16%, 0.04) to breasts, with a significant reduction in LAR (p = 0.03). CONCLUSIONS: FaB-VMAT significantly decreased the RR for CAD and CHF compared to B-VMAT, with almost the same overall risk of lung and breast cancer induction. These results are influenced by the different anatomical presentations, supporting the need for an individualized approach.

Survival Impact of Cardiac Dose Following Lung Stereotactic Body Radiotherapy.

INTRODUCTION: The purpose of this study was to determine the impact of radiation dose to substructures of the heart in lung stereotactic body radiotherapy (SBRT) patients on non-cancer-related deaths. METHODS: Patients treated with lung SBRT at a single institution from 2005 to 2013 were included. The heart and its substructures were contoured, and dose was calculated including mean, max, and max 10 cc dose. Clinical variables including stage, histology, age, gender, Charlson comorbidity index (CCI), preexisting cardiac disease, pulmonary function (forced expiratory volume in 1 second, diffusion capacity), and smoking status were explored for association with non-cancer-related deaths in univariable (UVA) and multivariable (MVA) analyses. Heart dosimetric parameters were correlated with the risk of radiation pneumonitis (RP) using UVA and MVA. RESULTS: A total of 189 patients were included with median age of 76 years (range, 48-93 years). Of these patients, 45.5% were female, 27.5% were T2, 16.9% were current smokers, 64% had preexisting cardiac risk factors, and 34.5% had CCI score of ≥ 3. Mean lung dose ± SD was 456 ± 231 cGy. Heart max, mean, and 10 cc doses were 1867 ± 1712 cGy, 265 ± 269 cGy, and 1150 ± 1075 cGy, respectively. There were 14 (7.4%) ≥ Grade 2 RP and 3 (1.6%) were ≥ Grade 3. The median overall survival was 37.3 months (95% confidence interval, 29.8-45.3 months). On UVA, female gender (P < .01), higher Eastern Cooperative Oncology Group (P = .01), cardiac risk (P < .01), CCI (P < .01), and bilateral ventricles max dose (P = .02) were associated with non-cancer-related deaths; on MVA, bilateral ventricles max dose was significant (P = .05). No heart parameters were associated with RP. CONCLUSIONS: Higher bilateral ventricles max dose is associated with poorer survival. Heart dose parameters should be considered when planning patients for SBRT.

Cardiac radiation dose distribution, cardiac events and mortality in early-stage lung cancer treated with stereotactic body radiation therapy (SBRT).

BACKGROUND: The impact of radiation dose to the heart in early-stage lung cancer patients treated with definitive stereotactic body radiation therapy (SBRT) is not well known. We, therefore, analyzed whether higher radiation dose to the heart would lead to an increase in cardiac toxicity and overall mortality. METHODS: Seventy-four patients with 75 tumors treated definitively with SBRT for early-stage non-small cell lung cancer (NSCLC) and two cases of limited-stage small cell lung cancer (SCLC) with an average follow-up of 35 months (range, 1-130 months) were retrospectively analyzed. The whole heart and cardiac substructures including atria, ventricles, heart valves, atrioventricular (AV) node and four major coronary artery branches were contoured using commercial treatment planning software. For each structure, multiple dose-volume parameters were recorded. The relation between radiation doses to the heart, tumor location, and preexisting medical conditions with the development of cardiac events and mortality was assessed. RESULTS: Overall, there was large variability in dose to cardiac substructures: mean heart dose (MHD) averaged 1.90 Gy (range, 0.04-11.00 Gy) equivalent 2 Gy dose (EQD2) and average max dose to the left anterior descending artery (LAD) was 5.67 Gy (range, 0.04-48.60 Gy) EQD2. Patients with tumor location in the upper lobes received higher cardiac radiation dose compared to other lobes (P<0.0001). There was no difference in MHD between central and peripheral tumor locations. The distance between heart and tumor was negatively associated with MHD (r=-0.61, P<0.0001). Eighteen patients developed cardiac complications including the need for defibrillator placement, arrhythmia development and worsening heart failure. Preexisting cardiac disease was associated with an increased number of cardiac events after radiotherapy (P=0.039). However, neither radiation dose to the whole heart or the cardiac substructures, nor comorbidities such as diabetes, hypercholesterolemia, hypertension or COPD were associated with the number of cardiac events or overall mortality. CONCLUSIONS: Radiation doses to the heart and its substructures show large variability. Cardiac events occurred more frequently in patients with a history of heart problems. At present, the effect of radiation dose on cardiac toxicity is unclear in patients undergoing SBRT for early-stage lung cancer. Longer follow-up and a larger cohort are needed to assess for late cardiac sequelae.

Dose to heart substructures is associated with non-cancer death after SBRT in stage I-II NSCLC patients.

BACKGROUND AND PURPOSE: To investigate potential associations between dose to heart (sub)structures and non-cancer death, in early stage non-small cell lung cancer (NSCLC) patients treated with stereotactic body radiation therapy (SBRT). METHODS: 803 patients with early stage NSCLC received SBRT with predominant schedules of 3×18Gy (59%) or 4×12Gy (19%). All patients were registered to an average anatomy, their planned dose deformed accordingly, and dosimetric parameters for heart substructures were obtained. Multivariate Cox regression and a sensitivity analysis were used to identify doses to heart substructures or heart region with a significant association with non-cancer death respectively. RESULTS: Median follow-up was 34.8months. Two year Kaplan-Meier overall survival rate was 67%. Of the deceased patients, 26.8% died of cancer. Multivariate analysis showed that the maximum dose on the left atrium (median 6.5Gy EQD2, range=0.009-197, HR=1.005, p-value=0.035), and the dose to 90% of the superior vena cava (median 0.59Gy EQD2, range=0.003-70, HR=1.025, p-value=0.008) were significantly associated with non-cancer death. Sensitivity analysis identified the upper region of the heart (atria+vessels) to be significantly associated with non-cancer death. CONCLUSIONS: Doses to mainly the upper region of the heart were significantly associated with non-cancer death. Consequently, dose sparing in particular of the upper region of the heart could potentially improve outcome, and should be further studied.

Heart dose associated with overall survival in locally advanced NSCLC patients treated with hypofractionated chemoradiotherapy.

Association of heart dose and overall survival was investigated in a cohort including 469 locally-advanced NSCLC patients receiving daily low-dose hypofractionated chemo-radiotherapy. Significant associations were found over a range of dose parameters. Multivariate analysis showed significant associations of heart_V2Gy:HR=1.007%-1 (95% CI:1.002-1.013; p=0.006), age:HR=1.026year-1 (1.011-1.042; p=0.001) and GTV volume:HR=1.001cc-1 (1.000-1.002; p=0.006) with overall survival.

The impact of high fructose on cardiovascular system: Role of α-lipoic acid.

The aim of this study was to evaluate the role of α-lipoic acid (α-LA) on oxidative damage and inflammation that occur in endothelium of aorta and heart while constant consumption of high-fructose corn syrup (HFCS). The rats were randomly divided into three groups with each group containing eight rats. The groups include HFCS, HFCS + α-LA treatment, and control. HFCS was given to the rats at a ratio of 30% of F30 corn syrup in drinking water for 10 weeks. α-LA treatment was given to the rats at a dose of 100 mg/kg/day orally for the last 6 weeks. At the end of the experiment, the rats were killed by cervical dislocation. The blood samples were collected for biochemical studies, and the aortic and cardiac tissues were collected for evaluation of oxidant-antioxidant system, tissue bath, and pathological examination. HFCS had increased the levels of malondialdehyde, creatine kinase MB, lactate dehydrogenase, and uric acid and showed significant structural changes in the heart of the rats by histopathology. Those changes were improved by α-LA treatment as it was found in this treatment group. Immunohistochemical expressions of tumor necrosis factor α and inducible nitric oxide synthase were increased in HFCS group, and these receptor levels were decreased by α-LA treatment. All the tissue bath studies supported these findings. Chronic consumption of HFCS caused several problems like cardiac and endothelial injury of aorta by hyperuricemia and induced oxidative stress and inflammation. α-LA treatment reduced uric acid levels, oxidative stress, and corrected vascular responses. α-LA can be added to cardiac drugs due to its cardiovascular protective effects against the cardiovascular diseases.

Clozapine-induced myocarditis in observational cross-sectional and follow-up evaluations: comparison with other antipsychotics in naturalistic settings / Miocarditis inducida por clozapina durante la evaluación observacional, transversal y longitudinal: comparación con otros antipsicóticos en ambientes naturalísticos

Myocarditis occurs more frequently during clozapine (CLZ) administration than during treatment with other antipsychotic drugs (APs). In this observational study, we transversally screened outpatients for myocarditis by comparing a CLZ group of 132 subjects, with a non-CLZ group taking other APs (n = 371) only, and in 21 CLZ-treated patients and 18 subjects treated with other APs who had been followed for more than one year. The protocol included a) assessment of symptoms such as dyspnea, tachycardia, chest discomfort, fever, cough, and edema, b) blood pressure and heart auscultation; c) a standard electrocardiogram after a 5-minute rest, d) white cell count, and qualitative determination of troponin I, creatine-kinase-MB and myoglobin, and e) a cardiologist evaluation of subjects with suspected myocarditis. Only one case of myocarditis was detected, providing an approximation of the frequency of myocarditis of 1.6% in the first month of treatment. This was a 30-year-old man with schizophrenia who developed symptoms at day 6 after starting a treatment with 200 mg of CLZ a day without titration. Myocarditis was not observed during prolonged CLZ or other AP administration. These results support the proposal of starting CLZ treatment with a low dose and the feasibility of a simple protocol for myocarditis detection in psychiatry primary care.

El desarrollo de miocarditis ocurre con más frecuencia durante el tratamiento con clozapina (CLZ) que durante el uso de otros antipsicóticos (APs). En el presente estudio observacional evaluamos la presencia de miocarditis mediante un protocolo transversal comparando 132 sujetos tratados con CLZ con 371 pacientes tratados con otro AP, y en 21 sujetos tratados con CLZ y 18 pacientes tratados con otro AP en un protocolo longitudinal mayor 1 año de duración. La evaluación incluyó: a) detección de síntomas como disnea, taquicardia, malestar torácico, fiebre, tos y edema; b) presión arterial y auscultación cardiaca; c) electrocardiograma estándar luego de un reposo de 5 minutos; d) contaje de glóbulos blancos y determinación cualitativa de troponina I, creatin-kinasa-MB y mioglobina, y e) evaluación por un cardiólogo en sujetos sospechosos para miocarditis. Detectamos un solo caso de miocarditis, lo que permite una aproximación sobre la frecuencia de miocarditis de 1,6 % durante el primer mes de tratamiento. Se trató de un sujeto masculino con esquizofrenia que desarrolló síntomas durante el día 6 después de haber iniciado el tratamiento con CLZ a la dosis de 200 mg por día sin titulación. No se detectaron sujetos sospechosos de miocarditis durante el tratamiento prolongado con CLZ u otro AP. Estos resultados sustentan la recomendación de comenzar el tratamiento con clozapina a dosis bajas, y la factibilidad de utilizar un protocolo sencillo para detectar miocarditis en la atención psiquiátrica primaria.

Lesão cardíaca secundária ao paraquat / Myocardial Lesion Due to Paraquat

Objetivo - Avaliar as alterações cardíacas na intoxicação exógena por paraquat. Métodos - Foi realizada análise dos dados clínicos e laboratoriais de 25 pacientes admitidos na UTI com intoxicação exógena por paraquat, de novembro de 1983 a janeiro de 1991. Resultados - A ingestão de paraquat ocorreu intencionalmente por tentativa de suicídio em 96% dos casos. A mortalidade foi de 56% com acometimento multisistêmico, nas seguintes freqüências: lesão pulmonar em 96%, lesão renal em 92%, lesão no trato gastrointestinal em 72%, alteração hepática em 56% e lesão cardíaca em 40%. Conclusão - A lesão cardíaca desencadeada pelo paraquat é freqüente (40%). A expressividade clínica das manifestações cardíacas é variável, mostrando desde alterações discretas no eletrocardiograma até necrose miocárdica aguda e maciça

Purpose - To evaluate cardiac alterations secondary to exogenous intoxication by paraquat. Methods - We performed analysis of clinical and laboratorial data of 25 patients with acute paraquat poisoning admitted in our ICU from November 1983 to January 1991. Results - There were purposeful overdoses in 24 cases (96%). The mortality rate was 56%. The lung involvement was 96%, renal was 92%, gastrointestinal tract was 72%, hepatic was 56%, and cardiac involvement was 40%. Conclusion - Cardiac involvement due to paraquat isfrequent (40%). The clinical picture of this involvement has a wide spectrum, ranging from minimal changes in the ECG to acute and extensive myocardial necrosis