Prognostic value of cardiovascular magnetic resonance left ventricular volumetry and geometry in patients receiving an implantable cardioverter defibrillator.

BACKGROUND: Current indications for implantable cardioverter defibrillator (ICD) implantation for sudden cardiac death prevention rely primarily on left ventricular (LV) ejection fraction (LVEF). Currently, two different contouring methods by cardiovascular magnetic resonance (CMR) are used for LVEF calculation. We evaluated the comparative prognostic value of these two methods in the ICD population, and if measures of LV geometry added predictive value. METHODS: In this retrospective, 2-center observational cohort study, patients underwent CMR prior to ICD implantation for primary or secondary prevention from January 2005 to December 2018. Two readers, blinded to all clinical and outcome data assessed CMR studies by: (a) including the LV trabeculae and papillary muscles (TPM) (trabeculated endocardial contours), and (b) excluding LV TPM (rounded endocardial contours) from the total LV mass for calculation of LVEF, LV volumes and mass. LV sphericity and sphere-volume indices were also calculated. The primary outcome was a composite of appropriate ICD shocks or death. RESULTS: Of the 372 consecutive eligible patients, 129 patients (34.7%) had appropriate ICD shock, and 65 (17.5%) died over a median duration follow-up of 61 months (IQR 38-103). LVEF was higher when including TPM versus excluding TPM (36% vs. 31%, p < 0.001). The rate of appropriate ICD shock or all-cause death was higher among patients with lower LVEF both including and excluding TPM (p for trend = 0.019 and 0.004, respectively). In multivariable models adjusting for age, primary prevention, ischemic heart disease and late gadolinium enhancement, both LVEF (HR per 10% including TPM 0.814 [95%CI 0.688-0.962] p = 0.016, vs. HR per 10% excluding TPM 0.780 [95%CI 0.639-0.951] p = 0.014) and LV mass index (HR per 10 g/m2 including TPM 1.099 [95%CI 1.027-1.175] p = 0.006; HR per 10 g/m2 excluding TPM 1.126 [95%CI 1.032-1.228] p = 0.008) had independent prognostic value. Higher LV end-systolic volumes and LV sphericity were significantly associated with increased mortality but showed no added prognostic value. CONCLUSION: Both CMR post-processing methods showed similar prognostic value and can be used for LVEF assessment. LVEF and indexed LV mass are independent predictors for appropriate ICD shocks and all-cause mortality in the ICD population.

Left atrial volume and function measured by cardiac magnetic resonance imaging as predictors of shocks and mortality in patients with implantable cardioverter-defibrillators.

Left atrial (LA) volume and function (LA ejection fraction, LAEF) have demonstrated prognostic value in various cardiovascular diseases. We investigated the incremental value of LA volume and LAEF as measured by cardiovascular magnetic resonance imaging (CMR) for prediction of appropriate implantable cardioverter defibrillator (ICD) shock or all-cause mortality, in patients with ICD. We conducted a retrospective, multi-centre observational cohort study of patients who underwent CMR prior to primary or secondary prevention ICD implantation. A single, blinded reader measured maximum LA volume index (maxLAVi), minimum LA volume index (minLAVi), and LAEF. The primary outcome was a composite of independently adjudicated appropriate ICD shock or all-cause death. A total of 392 patients were enrolled. During a median follow-up time of 61 months, 140 (35.7%) experienced an appropriate ICD shock or died. Higher maxLAVi and minLAVi, and lower LAEF were associated with greater risk of appropriate ICD shock or death in univariate analysis. However, in multivariable analysis, LAEF (HR 0.92 per 10% higher, 95% CI 0.81-1.04, p = 0.17) and maxLAVi (HR 1.02 per 10 ml/m2 higher, 95% CI 0.93-1.12, p = 0.72) were not independent predictors of the primary outcome. In conclusion, LA volume and function measured by CMR were univariate but not independent predictors of appropriate ICD shocks or mortality. These findings do not support the routine assessment of LA volume and function to refine risk stratification to guide ICD implant. Larger studies with longer follow-up are required to further delineate the clinical implications of LA size and function.

Serial Measurements of Left Ventricular Systolic and Diastolic Function by Cardiac Magnetic Resonance Imaging in Patients with Early Stage Breast Cancer on Trastuzumab.

Our aim was to evaluate the temporal changes in left ventricular (LV) diastolic filling in relation to other LV parameters using cardiac MRI (CMR) in patients with HER2 positive breast cancer receiving trastuzumab therapy. Fourty-one women with early stage HER2+ breast cancer underwent serial CMR (baseline, 6, 12, and 18 months) after initiation of trastuzumab therapy. A single, blinded observer measured LV parameters on de-identified CMRs in random order. Linear mixed models were used to investigate temporal changes. Compared to baseline, there were significant decreases in systolic function as measured by both left ventricular ejection fraction (LVEF) (p <0.001 at 6 and 12 months) and peak ejection rate corrected for end-diastolic volume (PER/LVEDV) (p = 0.008 at 6 months, p = 0.01 at 12 months). However, these differences were no longer significant at 18 months. In contrast, significant reductions in diastolic function as measured by LV peak filling rate corrected for end-diastolic volume (PFR/LVEDV) were observed at 6 months (p = 0.012), 12 months (p = 0.031), and up to 18 months (p = 0.034). There were no significant temporal changes in the time to peak filling rate corrected for cardiac cycle (TPF/RR). The reduction in PFR/LVEDV at 18 months was no longer significant when corrected for heart rate. In conclusion, there were significant subclinical deleterious effects on both LV systolic and diastolic function among patients receiving trastuzumab. While there was recovery in LV systolic function after therapy cessation at 18 months, reduction in PFR/LVEDV appeared to persist. Thus, diastolic dysfunction may serve as a marker of trastuzumab-induced cardiotoxicity that needs to be confirmed in a larger study.

Magnetic resonance imaging as an adjunct to computed tomography in the diagnosis of pulmonary Hydatid cysts.

INTRODUCTION: Although pulmonary hydatid cysts can be diagnosed on computed tomography (CT), sometimes findings can be atypical. Other hypodense infective or neoplastic lesions may mimic hydatid cysts. We proposed that magnetic resonance imaging (MRI) may act as a problem-solving tool, aiding the definite diagnosis of hydatid cysts and differentiating it from its mimics. The aim of this study is to assess the findings of pulmonary hydatid cysts on CT and MRI and the additional contribution of MRI in doubtful cases. MATERIALS AND METHODS: This is a retrospective study of 90 patients with suspected hydatid cysts. CT and MRI findings were noted and role of MRI in diagnosing hydatid cysts and its mimics was studied. Descriptive statistics for CT findings and sensitivity and specificity of MRI were calculated using surgery or histopathology as gold standard. RESULTS: Of the 90 patients with suspected pulmonary hydatid cysts, there were 52 true-positive and 7 false-positive cases on CT. Commonest CT finding was unilocular thick-walled cyst. In the 26 patients who had additional MRI, based on T2-weighted hypointense rim or folded membranes, accurate preoperative differentiation of 14 patients with hydatid cysts from 10 patients with alternate diagnosis was possible. There was one false-positive and one false-negative case on MRI. CONCLUSION: Although hydatid cyst can be diagnosed on CT on most occasions, sometimes there are challenges with certain mimics and atypical appearances. T2-weighted MRI can act as a problem solving tool to conclusively diagnose hydatid cyst or suggest an alternate diagnosis.

Myocardial nulling pattern in cardiac amyloidosis on time of inversion scout magnetic resonance imaging sequence - A new observation of temporal variability.

CONTEXT: The pattern of myocardial nulling in the inversion scout sequence [time of inversion scout (TIS)] of cardiac magnetic resonance imaging (MRI) is an accurate tool to detect cardiac amyloidosis. The pattern of nulling of myocardium and blood at varying times post gadolinium injection and its relationship with left ventricular mass (LVM) in amyloidosis have not been described previously. AIMS: The aim is to study the nulling pattern of myocardium and blood at varying times in TIS and assess its relationship with LVM and late gadolinium enhancement (LGE) in amyloidosis. MATERIALS AND METHODS: This was a retrospective study of 109 patients with clinical suspicion of cardiac amyloidosis who underwent MRI. Of these, 30 had MRI features of amyloidosis. The nulling pattern was assessed at 5 (TIS5min) and 10 (TIS10min) minutes (min) post contrast injection. Nulling pattern was also assessed at 3min (TIS3min) in four patients and 7min (TIS7min) in five patients. Myocardial mass index was calculated. Mann-Whitney U test was done to assess statistical difference in the myocardial mass index between patients with and without reversed nulling pattern (RNP) at TIS5min. RESULTS: RNP was observed in 58% at TIS5min and 89.6% at TIS10min. Myocardial mass index was significantly higher in patients with RNP at TIS5min[mean = 94.87 g/m2; standard deviation (SD) =17.63) when compared with patients with normal pattern (mean = 77.61 g/m2; SD = 17.21) (U = 18; P = 0.0351). CONCLUSION: In cardiac amyloidosis, TIS sequence shows temporal variability in nulling pattern. Earlier onset of reverse nulling pattern shows a trend toward more LVM and possibly more severe amyloid load.

Left ventricular structure and diastolic function by cardiac magnetic resonance imaging in hypertrophic cardiomyopathy.

OBJECTIVE: Diastolic dysfunction is common in hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD), but its relationships with left ventricular (LV) parameters have not been well studied. Our objective was to assess the relationship of various measures of diastolic function, and maximum left ventricular wall thickness (MLVWT) and left ventricular mass index (LVMI) in HCM, HHD and normal controls using cardiac magnetic resonance imaging (CMR). We also assessed LV parameters and diastolic function in relation to late gadolinium enhancement (LGE) and right ventricular (RV) hypertrophy in HCM. METHODS: 41 patients with HCM, 21 patients with HHD and 20 controls were studied. Peak filling rate (PFR), time to peak filling (TPF), MLVWT and LVMI were measured using CMR. LGE and RV morphology were assessed in HCM patients. RESULTS: MLVWT correlated with TPF in HCM (r=0.38; p=0.02), HHD (r=0.58; p=0.01) and controls (r=0.54; p=0.01); correlation between MLVWT and TPF was weaker in HCM than HHD. LVMI did not correlate with diastolic function. In HCM, LGE extent correlated with MLVWT (τ=0.41; p=0.002) and with TPF (τ=0.29; p=0.02). The HCM patients with RV hypertrophy had higher MLVWT (p<0.001) and TPF (p=0.03) than patients without RV hypertrophy. CONCLUSION: MLVWT correlates with diastolic function (TPF) in HCM, HHD and controls. LVMI did not show significant correlation with TPF. The diastolic dysfunction in HCM is not entirely explained by wall thickening. LGE and RV involvement are associated with worse LV diastolic function, suggesting that these may be markers of more severe underlying myocardial disarray and fibrosis that contribute to diastolic dysfunction.

A simplified staging system based on the radiological findings in different stages of ochronotic spondyloarthropathy.

This study describes a group of 26 patients with ochronotic spondyloarthropathy who were on regular treatment and follow-up at a tertiary level hospital and proposes a simplified staging system for ochronotic spondyloarthropathy based on radiographic findings seen in the thoracolumbar spine. This proposed classification makes it easy to identify the stage of the disease and start the appropriate management at an early stage. Four progressive stages are described: an inflammatory stage (stage 1), the stage of early discal calcification (stage 2), the stage of fibrous ankylosis (stage 3), and the stage of bony ankylosis (stage 4). To our knowledge, this is the largest reported series of radiological description of spinal ochronosis, and emphasizes the contribution of the spine radiograph in the diagnosis and staging of the disease.

Unusual mediastinal cystic lesions with air fluid level.

An air-fluid level within an enlarged mediastinal lymph node is unusual. We describe three patients who had mediastinal lymphadenopathy containing air-fluid levels. The differential diagnosis and approach are discussed.