Left Ventricular Myocardial Dysfunction Evaluation in Thalassemia Patients Using Echocardiographic Radiomic Features and Machine Learning Algorithms.

Heart failure caused by iron deposits in the myocardium is the primary cause of mortality in beta-thalassemia major patients. Cardiac magnetic resonance imaging (CMRI) T2* is the primary screening technique used to detect myocardial iron overload, but inherently bears some limitations. In this study, we aimed to differentiate beta-thalassemia major patients with myocardial iron overload from those without myocardial iron overload (detected by T2*CMRI) based on radiomic features extracted from echocardiography images and machine learning (ML) in patients with normal left ventricular ejection fraction (LVEF > 55%) in echocardiography. Out of 91 cases, 44 patients with thalassemia major with normal LVEF (> 55%) and T2* ≤ 20 ms and 47 people with LVEF > 55% and T2* > 20 ms as the control group were included in the study. Radiomic features were extracted for each end-systolic (ES) and end-diastolic (ED) image. Then, three feature selection (FS) methods and six different classifiers were used. The models were evaluated using various metrics, including the area under the ROC curve (AUC), accuracy (ACC), sensitivity (SEN), and specificity (SPE). Maximum relevance-minimum redundancy-eXtreme gradient boosting (MRMR-XGB) (AUC = 0.73, ACC = 0.73, SPE = 0.73, SEN = 0.73), ANOVA-MLP (AUC = 0.69, ACC = 0.69, SPE = 0.56, SEN = 0.83), and recursive feature elimination-K-nearest neighbors (RFE-KNN) (AUC = 0.65, ACC = 0.65, SPE = 0.64, SEN = 0.65) were the best models in ED, ES, and ED&ES datasets. Using radiomic features extracted from echocardiographic images and ML, it is feasible to predict cardiac problems caused by iron overload.

Global longitudinal strain for detection of cardiac iron overload in patients with thalassemia: a meta-analysis of observational studies with individual-level participant data.

BACKGROUND: Although cardiac magnetic resonance (CMR) is the most reliable tool for assessment of CIO in patients with thalassemia, it is not always readily available. Recent studies have explored the potential of GLS as an alternative for diagnosis of CIO. We aimed to investigate the efficacy of global longitudinal strain (GLS) for detection of cardiac iron level (CIO). METHODS: We searched SCOPUS, MEDLINE, and Embase to identify the studies which used GLS for assessment of CIO. We searched for individual participant data (IPD) in eligible studies to perform ROC curve analysis. CMR with a T2* cut-off value of 20 ms was considered as the gold standard. A meta-analysis was performed and the risk of bias was assessed using the JBI Checklist. RESULTS: A total of 14 studies with 789 thalassemia patients (310 and 430 with and without CIO respectively and 49 with undetermined condition) were considered eligible for meta-analysis. IPDs of 405 participants were available. GLS was significantly lower in patients with CIO (-17.5 ± 2.7%) compared to those without CIO (-19.9 ± 2.3%; WMD = 1.6%, 95% CI = [0.76-2.4], p = 0.001, I2 = 77.1%) and to normal population (-20.61 ± 2.26%; WMD = 2.2%, 95% CI = [0.91-3.5], p = 0.001, I2 = 83.9%). A GLS < -19.5% could predict CIO with 92.8% sensitivity and 34.63% specificity (AUC = 0.659, 95% CI = [0.6-0.72], p-value < 0.0001). A GLS value < -6% has 100% positive predictive and ≥ -24.5% has 100% negative predictive values for detection of CIO. CONCLUSIONS: According to our study, GLS is a strong predictor of CIO and when CMR is not available, it may be a useful screening method for identification of CIO in thalassemia patients.

The predictive role of cardiac magnetic resonance imaging in determining thalassemia patients with intermediately to highly probable pulmonary hypertension.

OBJECTIVES: We sought to determine the cardiac magnetic resonance (CMR) indicators of intermediately to highly probable pulmonary hypertension (IHpPH) in patients with thalassemia referred for myocardial iron overload assessments to prevent further cardiac complications. METHODS: The study population consisted of 152 patients with thalassemia (major or intermedia) (49.3% women, mean age = 33 ± 10.1 years) who underwent non-contrast CMR and echocardiographic examinations on the same day. Functional, T2*, and global strain parameters via a feature-tracking method were extracted from CMR. The probability of PH was defined based on the tricuspid regurgitation velocity and echocardiographic parameters. The catheterization-derived hemodynamic data of patients with moderate to high probable PH was registered. RESULTS: Twenty-two (14.5%) patients suffered from IHpPH. The multivariate logistic regression analysis revealed that the right ventricular end-systolic volume index (RVESVI) was the strongest of all the CMR parameters for the prediction of IHpPH (OR: 1.044, 95% CI: 1.021-1.067). The other powerful IHpPH predictor was age (OR: 1.066, 95% CI: 1.009-1.126). A cutoff point of greater than 47 ml for RVESVI (AUC: .801, 95% CI: .728-.861) was found to predict IHpPH with 73.91% sensitivity and 70.31% specificity. The single most robust CMR-derived strain parameter for IHpPH prediction was the right ventricular global longitudinal strain (OR: .887, 95% CI: .818-.961). A p value of less than 0.05 was considered significant. CONCLUSIONS: Both CMR functional and global strain parameters were strong predictors of IHpPH in our patients with thalassemia.

The role of echocardiography in anomalous origin of coronary artery from pulmonary artery (ALCAPA): Simple tool for a complex diagnosis.

Anomalous origin of coronary artery from pulmonary artery (ALCAPA) is a rare coronary anomaly usually presenting in the first year of life. Adult presentation suggests a wide range of differential diagnosis such as myocarditis, dilated cardiomyopathy, and coronary artery disease. We have presented here the major distinctive echocardiographic features of ALCAPA through 4 cases. Since echocardiography is often used as the first imaging modality in these clinical scenarios, recognizing the characteristics of ALCAPA in a routine echocardiographic examination can transform a readily available, low-cost tool into a valuable discriminative modality.

The Role of Exercise Stress Echocardiography for Determination of Subclinical Cardiac Involvement in ß-Thalassemia Major.

ß-Thalassemia major (ß-TM) patients are at increased risk for cardiovascular diseases. Determination of subclinical cardiac involvement is essential for preventive measures. Thus, we aimed to evaluate the role of stress echocardiography for identification of subclinical cardiac dysfunction in ß-TM patients. In this prospective study, 45 ß-TM patients who were referred for cardiac evaluation, were enrolled. Exclusion criteria included non sinus rhythm and overt cardiac disease. Stress echocardiography levels and cardiac magnetic resonance imaging (MRI) results were obtained from ß-TM patients. Patients were divided into two groups of normal vs. iron overload from cardiac T2* greater or less than 20 msec, respectively. Resting and peak exercise right ventricular stroke volume (RVSV) and left ventricular SV (LVSV) were significantly lower in iron overload vs. normal ß-TM patients, respectively (p value <0.05). At peak LV global longitudinal strain (GLS) and myocardial performance index (MPI) were significantly decreased and increased compared with resting in iron overload vs. normal ß-TM patients, respectively (p value <0.05). There was a significant relationship between inappropriate hemodynamic response to exercise and lower age (p value = 0.032). Resting LVSV and RVSV seemed better prognosticators for iron overload than LV ejection fraction (LVEF). Decreased GLS and increased MPI at peak exercise could also predict the presence of cardiac iron overload. These measurements by stress echocardiography could be evaluated when cardiac T2* could not be determined.

Peri-mitral ventriculoatrial fistula after blunt thoracic trauma.

Blunt trauma to the chest can damage any thoracic organ. Heart valve damage and particularly mitral apparatus occurs relatively rare, and the patients are expected to become acutely symptomatic. However, in patients with multiple traumas, other dominant severe damages tend to draw away the attention of the physicians resulting in neglect of less salient heart injuries. Here, we present a patient with history of blunt chest trauma and incidental finding of posttraumatic severe mitral regurgitation.

Unusual collateral vessel from right subclavian vein to left atrium, a rare complication of superior vena cava obstruction.

The most commonly reported collateral systems in the setting of superior vena cava obstruction are azygos venous system, vertebral venous system, external and internal thoracic venous system based on McLntire and Sykes classification. A 49-year-old female with renal disease complained dyspnea on exertion. Transesophageal echocardiography showed significant mitral annular calcification, large multi-lobulated mass at posterior aspect of RA, and complete obstruction of superior vena cava by thrombus formation. Computed tomography angiography showed a collateral vein to the left atrium (LA) roof. This case report is the first one which shows development of collateral vein from right subclavian to LA.

The correlation between cardiac magnetic resonance T2* and left ventricular global longitudinal strain in people with ß-thalassemia.

BACKGROUND: Heart failure is the biggest cause of mortality and morbidity in people with thalassemia, and iron deposition in cardiac tissue impairs cardiovascular function. Therefore, early detection of cardiac involvement is important to improve the prognosis in these individuals. METHOD: Two- and three-dimensional echocardiography was performed to evaluate left ventricular ejection fraction (LVEF), left ventricular volumes and diameters, and global longitudinal strain (GLS) in 130 individuals with ß-thalassemia using the speckle tracking method. Magnetic resonance imaging (MRI) was carried out on both the heart and liver. The participants were divided into 2 groups based on cardiac T2* values (normal and abnormal cardiac iron load), and the correlation between cardiac T2* MRI and GLS was evaluated. RESULTS: The statistical analysis showed a significant correlation between cardiac T2* MRI and left ventricular global longitudinal strain. There was a significant difference in global longitudinal strain (P < .0001), liver MRI T2*( P < .0001), and left ventricular ejection fraction (P < .001) between the 2 groups. The optimal cutoff value for GLS was -18.5% with sensitivity and specificity 73.0% and 63.0%, respectively (postitive predictive value = 50%, negative predictive value = 82.3%, AUC = 0.742, std. error = 0.046) which predicts T2* value of <20 ms, according to cardiac MRI. CONCLUSIONS: The participants with cardiac iron overload had a lower GLS than those without one. This suggests that GLS may be a useful method to predict myocardial iron overload particularly in ß-thalassemia patients with subclinical cardiac involvement.

Subclinical systolic and diastolic dysfunctions in patients with metabolic syndrome and angiographically normal coronary arteries: An echocardiographic study.

BACKGROUND: The metabolic syndrome (MetS), as a combination of cardiovascular risk factors, is associated with subclinical cardiovascular diseases. We sought to evaluate the subclinical myocardial dysfunctions using echocardiography in patients with normal coronary arteries. MATERIALS AND METHODS: In this cross-sectional study, we assessed 50 consecutive patients with angiographically-proven normal coronary arteries and a left ventricular (LV) ejection fraction (EF) ≥55%. The diagnosis of MetS was based on the National Cholesterol Education Program/Adult Treatment Panel III criteria. All patients were examined using conventional and two-dimensional speckle tracking echocardiography for evaluating the myocardial functions. RESULTS: The patients' mean age was 52.3 ± 8.3 years with 32 females (64%). LV EF, mass index, and full volume were comparable between groups. The LV myocardial performance index (0.40 ± 0.13 vs. 0.32 ± 0.10; P = .027), global longitudinal strain (GLS, -15.8 ± 4.5 vs. -19.7 ± 2.1; P < .001), and global circumferential strain (-17.9 ± 6.1 vs. -21.5 ± 3.3; P = .014) were different between patients with or without MetS, respectively. The GLS discriminated patients with MetS (area under the curve = 0.837, sensitivity 80%, specificity 88%, P < .001). CONCLUSIONS: In MetS without coronary artery disease, echocardiography demonstrated subclinical systolic and diastolic dysfunction.

Silent Pulmonary Artery Dissection in a patient with old Pulmonary Balloon Valvuloplasty.

Percutaneous pulmonary balloon valvuloplasty (PBV) remains the treatment of choice for pulmonary stenosis (PS). This procedure is effective, safe and gives excellent results. Pulmonary artery (PA) dissection is a rare complication of PBV. This report is a case of an asymptomatic 17-year-old male with a history of PBV due to severe PS dating back to fifteen years ago. During recent echocardiography, an intimal flap was detected in the main PA and entry site was clearly seen by contrast study.

A rare association of the absence of left pulmonary artery with ventricular septal defect, pulmonary hypertension, and more interestingly, patent ductus arteriosus in an adult patient: Case report and literature review.

Key Clinical Message: In this study, we introduced one of the rarest concomitants of the absence of left pulmonary artery (LPA), which was seen in our patient along with patent ductus arteriosus (PDA) and ventricular septal defect (VSD). Abstract: Unilateral absence of pulmonary artery (UAPA) is a congenital heart disease in association with other abnormalities such as tetralogy of Fallot and septal defects or isolated in 30% of cases and occurs in the right lung in two thirds of cases. Our case is a 33-year-old man who was hospitalized with symptoms of cough, shortness of breath, and hemoptysis. The echocardiography revealed a large ventricular septal defect, absent left pulmonary artery, and severe pulmonary hypertension (PH) along with patent ductus arteriosus. These findings were confirmed by CT angiography. This association has rarely been found in past studies. Due to PH and pulmonary infection, the patient was treated with intravenous prostaglandin and antibiotics. However, in cases of timely diagnosis and treatment of UAPA, fatal complications such as pulmonary hypertension, morbidity, and mortality are reduced. This case emphasizes the importance of awareness of this abnormality and its associated anomalies to enable early diagnosis and treatment.

The effect of significant weight loss after bariatric surgery on echocardiographic indices: an observational study focusing on left ventricular deformation by 2D speckle echocardiography and right ventricular size.

BACKGROUND: Obesity is a known risk factor for atherosclerosis and cardiac disease. HYPOTHESIS: This study evaluated the effect of significant weight loss following bariatric surgery on myocardial deformation indices and right ventricular size (RV). This was a prospective cohort study. Morbid obese patients scheduled for bariatric surgery from July 2017 to February 2018 at Firoozgar Hospital were included in our study and referred for transthoracic echocardiography at Rajaie Cardiovascular Medical and Research Center. RESULTS: Thirty-four patients entered the study. The absolute value of global longitudinal strain (GLS) at baseline, 3, and 6 months after surgery was 17.42 ± 2.94%, 18.24 ± 3.09%, and 19.52 ± 2.78%, respectively, with a statistically significant difference from baseline to after six months (P value < 0.001). The absolute value of global circumferential strain (GCS) at baseline, 3, and 6 months after surgery was 20.14 ± 4.22%, 23.32 ± 4.66%, and 24.53 ± 4.52%, respectively, with statistically significant changes (P value < 0.001) from baseline to three months and from baseline to six months and no significant difference from three months to six months. A significant decrease was reported in mechanical dispersion of circumferential strain (38.05 ± 23.81-23.37 ± 20.86 ms, P value = 0.006) 6 months after surgery. Right ventricular size three- and six-month post-surgery showed a significant decrease relative to baseline echocardiography. CONCLUSIONS: Bariatric surgery could enhance cardiac function, as proven by 2D speckle echocardiography. Changes in RV size may be related to weight loss and should be considered when assessing patients who have undergone bariatric surgery.

Uncommon manifestation of Ebstein anomaly: A case report of apical displacement involving all tricuspid valve leaflets.

Key Clinical Message: This case report presents an uncommon variant of Ebstein anomaly, where all three tricuspid valve leaflets exhibited apical displacement-a rare finding. It illustrates the complexities in diagnosing and managing such atypical presentations, with successful surgical correction through annuloplasty. The report adds valuable insights to the limited literature on this congenital heart disease. Abstract: Ebstein anomaly (EA), a rare congenital heart disorder, presents with diverse clinical spectrums. This case report explores a distinctive manifestation of EA, where all three tricuspid valve (TV) leaflets exhibited apical displacement, highlighting a novel aspect in the presentation of this condition. A 44-year-old woman, under long-term medical surveillance for EA, showcased an atypical clinical trajectory marked by the apical displacement of all TV leaflets, which is uncommon in EA. Despite a predominantly asymptomatic course, recent exacerbation of symptoms prompted further evaluation. Diagnostic modalities, including echocardiography and cardiac magnetic resonance imaging, revealed severe tricuspid regurgitation concomitant with unprecedented apical displacement of the anterior, septal, and posterior tricuspid leaflets. The displacement of the anterior leaflet was contrary to typical embryonic valvular formation expectations, indicating a unique presentation within EA. The patient underwent annuloplasty surgery, which successfully rectified the anomalous TV architecture. Postoperative evaluation demonstrated mild residual tricuspid regurgitation, and the patient was discharged in stable condition. This case underscores the variability in EA presentations and accentuates the significance of tailored surgical interventions. The observation of apical displacement involving all TV leaflets adds a unique dimension to the existing EA literature, reinforcing the need for careful diagnosis and personalized treatment approaches.

Role of feature tracking cardiac magnetic resonance imaging in early detection of cardiac dysfunction in ß-thalassemia patients recovered from COVID-19: A cross-sectional study.

Background and Aims: ß-Thalassemia patients may have cardiac complications due to iron overload, which puts them at higher risk of cardiac complications induced by coronavirus disease 2019 (COVID-19) compared with the normal population. The present study aims to evaluate early cardiovascular complications following iron overload in ß-thalassemia patients who had early recovery from COVID-19 by cardiac magnetic resonance imaging (MRI) and feature-tracking technique. Methods: Thirty-two confirmed COVID-19-recovered ß-thalassemia cases were evaluated within 3 weeks to 3 months after a positive reverse-transcriptase polymerase chain reaction COVID-19 test. Both the heart and liver of all patients were examined using cardiac MRI. Results: We analyzed 32 patients with mean age of 32.84 ± 6.45 years at baseline. Left ventricular global strain values were significantly associated with myocardial T2*. A cut-off value of -15.08% for global longitudinal strain (GLS) with sensitivity and specificity of 90% and 61.1% (p = 0.017), 32.33% for global radial strain (GRS) with sensitivity and specificity of 80% and 94.4% (p = 0.001) and -16.21 for global circumferential strain (GCS), with sensitivity and specificity of 80% and 89.9% (p = 0.013) may indicate cardiac iron overload. Conclusion: GLS, GRS, and GCS were significantly decreased in patients with myocardial T2* <20 ms (iron overload), while no significant change was observed in the right and left ventricular ejection fraction (RV- and LVEF). Cardiac MRI feature-tracking may be helpful in the early detection of cardiac complications resulting from iron overload in ß-thalassemia patients who had early recovery from COVID-19.

The Effect of L-Arginine Oral Supplementation on the Improvement of Cardiovascular Function and Pulmonary Artery Pressure in Patients with Major and Intermedia ß-Thalassemia.

Background: Thalassemia is the most common inherited anemia in worldwide. Heart failure is the most common cause of mortality and morbidity in patients with major and intermedia ß-thalassemia. This study aimed to evaluate the effect of oral administration of L-arginine on the improvement of systolic Pulmonary Artery Pressure (PAP) and cardiac function in patients with major and intermedia ß-thalassemia. Methods: This randomized clinical trial was done on 88 patients with ß-thalassemia admitted to Ali Asghar Hospital, Tehran, Iran between 2020 and 2021. Echocardiography was performed for all the patients before the intervention. Afterwards, the patients were randomly divided into two groups of placebo and L-arginine. The patients underwent echocardiography after eight weeks and were compared with respect to the results. Results: The mean blood transfusion interval was 20.21 d in the placebo group and 17.14 d in the L-arginine group (P=0.082). The results revealed no significant difference between the two groups regarding the mean levels of Hemoglobin (Hb) and ferritin, frequency of splenectomy. However, the mean PAP significantly decreased from 32.88 to 26.02 in the L-arginine group (P=0.009), but did not change in the placebo group. Nonetheless, no significant change was observed in the mean Ejection Fraction (EF) before and after L-arginine administration. Conclusion: L-arginine administration prevented the increase of PAP and was effective in preventing cardiovascular disorders including increased systolic PAP in patients with major and intermedia B-thalassemia. However, the results have to be confirmed in further studies with larger sample sizes.

In-silico investigations of haemodynamic parameters for a blunt thoracic aortic injury case.

Accounting for 1.5% of thoracic trauma, blunt thoracic aortic injury (BTAI) is a rare disease with a high mortality rate that nowadays is treated mostly via thoracic endovascular aortic repair (TEVAR). Personalised computational models based on fluid-solid interaction (FSI) principals not only support clinical researchers in studying virtual therapy response, but also are capable of predicting eventual outcomes. The present work studies the variation of key haemodynamic parameters in a clinical case of BTAI after successful TEVAR, using a two-way FSI model. The three-dimensional (3D) patient-specific geometries of the patient were coupled with three-element Windkessel model for both prior and post intervention cases, forcing a correct prediction of blood flow over each section. Results showed significant improvement in velocity and pressure distribution after stenting. High oscillatory, low magnitude shear (HOLMES) regions require careful examination in future follow-ups, since thrombus formation was confirmed in some previously clinically reported cases of BTAI treated with TEVAR. The strength of swirling flows along aorta was also damped after stent deployment. Highlighting the importance of haemodynamic parameters in case-specific therapies. In future studies, compromising motion of aortic wall due to excessive cost of FSI simulations can be considered and should be based on the objectives of studies to achieve a more clinical-friendly patient-specific CFD model.

Multimodality imaging in the diagnostic approach to a patient with carcinoid heart disease involving four heart valves.

Carcinoid heart disease is a rare condition that occurs in less than half of patients with carcinoid syndrome. The disease mainly affects right-sided heart valves; however, in 5%-10%, it can also involve left-sided valves. This case illustrates the most complicated form of the disease involving four heart valves.

A rare cause of complete heart block in an adult: Primary cardiac lymphoma.

Primary cardiac lymphoma (PCL) is a rare primary cardiac neoplasm with a relatively poor prognosis despite confinement to the heart and/or pericardium. We report a 54-year-old man who had presented with complete heart block for which he had undergone permanent pacemaker implantation, and six months later he was referred to us for evaluation of progressive exertional dyspnea. Multislice spiral computed tomography angiography of the heart and major vasculature showed infiltrative tumoral lesion that has involved interatrial septum, right atrium, left atrium, and left ventricle with invasion into the pulmonary artery. Tissue samples were taken using uniportal video-assisted thoracoscopic surgery, and the histologic examination revealed diffuse large B-cell lymphoma. Chemoimmunotherapy was effective in inducing tumor regression and the patient was still in remission during the next six months after treatment.

RIvaroxaban in mitral stenosis (RISE MS): A pilot randomized clinical trial.

BACKGROUND: Patients with moderate-to-severe mitral stenosis (MS) have bee excluded from all major randomized controlled trials (RCTs) comparing non-vitamin K antagonist oral anticoagulants (NOACs) with warfarin in patients with atrial fibrillation (AF). METHODS AND RESULTS: In this pilot RCT, 40 patients were randomized to rivaroxaban 20 mg daily or warfarin. No patients experienced symptomatic ischemic strokes and systemic embolic events (the primary composite study outcome) during a 12-month follow-up. No major bleeding was reported. During the follow-up, 18.2% of patients in both groups showed echocardiographic signs of increased thrombogenicity in the left atrial appendage. The rate of silent cerebral ischemia was 13.3% in the rivaroxaban group and 17.6% in the warfarin group at brain magnetic resonance imaging. CONCLUSION: Our results suggest acceptable efficacy and safety for rivaroxaban in patients with AF and moderate-to-severe MS and are encouraging for larger RCTs in this so far neglected setting (NCT03926156).

Fast vs. ultraslow thrombolytic infusion regimens in patients with obstructive mechanical prosthetic valve thrombosis: a pilot randomized clinical trial.

AIMS: Thrombolysis is an alternative to surgery for mechanical prosthetic valve thrombosis (MPVT). Randomized clinical trials have yet to test the safety and efficacy of a proposed ultraslow thrombolytic infusion regimen. METHODS AND RESULTS: This single-centre, open-label, pilot randomized clinical trial randomized adult patients with acute obstructive MPVT to an ultraslow thrombolytic regimen [25 mg of recombinant tissue-type plasminogen activator (rtPA) infused in 25 h] and a fast thrombolytic regimen (50 mg of rtPA infused in 6 h). If thrombolysis failed, a repeated dose of 25 mg of rtPA for 6 h was administered in both groups up to a cumulative dose of 150 mg or the occurrence of a complication. The primary outcome was a complete MPVT resolution (>75% fall in the obstructive gradient by transthoracic echocardiography, <10° limitation in opening and closing valve motion angles by fluoroscopy, and symptom improvement). The key safety outcome was a Bleeding Academic Research Consortium type III or V major bleeding. Overall, 120 patients, including 63 (52.5%) women, at a mean age of 36.3 ± 15.3 years, were randomized. Complete thrombolysis success was achieved in 51 patients (85.0%) in the ultraslow-regimen group and 47 patients (78.3%) in the fast-regimen group [odds ratio 1.58; 95% confidence interval (CI) 0.25-1.63; P = 0.34]. One case of transient ischaemic attack and three cases of intracranial haemorrhage (absolute risk difference -6.6%; 95%CI -12% -0.3%; P = 0.07) were observed only in the fast-regimen group. CONCLUSION: The ultraslow thrombolytic regimen conferred a high thrombosis resolution rate without major complications. Such findings should be replicated in more adequately powered trials.