Milind Y. Desai

2012 ACCF/AATS/SCAI/STS expert consensus document on transcatheter aortic valve replacement.

Robert A. Harrington, MD, FACC, Chair Deepak L. Bhatt, MD, MPH, FACC, Vice Chair Victor A. Ferrari, MD, FACC John D. Fisher, MD, FACC Mario J. Garcia, MD, FACC Timothy J. Gardner, MD, FACC Federico Gentile, MD, FACC Michael F. Gilson, MD, FACC Adrian F. Hernandez, MD, FACC Alice K. Jacobs

ACCF/SCCT/ACR/AHA/ASE/ASNC/NASCI/SCAI/SCMR 2010 Appropriate Use Criteria for Cardiac Computed Tomography

The American College of Cardiology Foundation (ACCF), along with key specialty and subspecialty societies, conducted an appropriate use review of common clinical scenarios where cardiac computed tomography (CCT) is frequently considered. The present document is an update to the original CCT/cardiac magnetic resonance (CMR) appropriateness criteria published in 2006, written to reflect changes in test utilization, to incorporate new clinical data, and to clarify CCT use where omissions or lack of clarity existed in the original criteria (1). The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Ninety-three clinical scenarios were developed by a writing group and scored by a separate technical panel on a scale of 1 to 9 to designate appropriate use, inappropriate use, or uncertain use. In general, use of CCT angiography for diagnosis and risk assessment in patients with low or intermediate risk or pretest probability for coronary artery disease (CAD) was viewed favorably, whereas testing in high-risk patients, routine repeat testing, and general screening in certain clinical scenarios were viewed less favorably. Use of noncontrast computed tomography (CT) for calcium scoring was rated as appropriate within intermediate- and selected low-risk patients. Appropriate applications of CCT are also within the category of cardiac structural and functional evaluation. It is anticipated that these results will have an impact on physician decision making, performance, and reimbursement policy, and that they will help guide future research.

Statin-Induced Cholesterol Lowering and Plaque Regression After 6 Months of Magnetic Resonance Imaging–Monitored Therapy

Background—Statin therapy reduces adverse outcomes, with a minimal decrease in vessel stenosis. Magnetic resonance imaging (MRI) noninvasively detects atherosclerotic plaque (AP) reduction. We hypothesized that statin-induced AP regression can be monitored by MRI and detected earlier than previously reported and is significantly associated with its lipid-lowering effect. Methods and Results—APs in thoracic aorta were measured by combined surface/transesophageal MRI in 27 patients (treated with simvastatin 20 to 80 mg daily) before and after 6 months of therapy. AP volume and luminal dimensions were measured from 6 cross sections used to construct a 2.4-cm 3D volume of the aorta that included plaque and lumen. Method reproducibility was studied in 10 patients imaged twice, 1 week apart. AP volume was reduced from 3.3±0.1.4 to 2.9±1.4 cm3 at 6 months (P<0.02), whereas luminal volume increase was less accentuated (from 12.0±3.9 to 12.2±3.7 cm3, P<0.06). LDL cholesterol decreased by 23% (from 125±32 to 97±27 mg/dL, P<0.05) in 6 months. AP regression (plaque volume/area reduction) was significantly related to LDL cholesterol reduction (P<0.02 and P<0.005, respectively), and luminal volume increase was inversely related to LDL cholesterol reduction (P<0.04). Plaque volume measurement was highly reproducible (intraclass correlation R=0.98 and variability=4.8%). Intraobserver (0.91) and interobserver (0.81) concordances were documented for plaque volume assessment. Conclusions—AP regression and reverse remodeling can be detected accurately by MRI 6 months after statin therapy initiation, and it is strongly associated with LDL cholesterol reduction.

B1-insensitive T2 preparation for improved coronary magnetic resonance angiography at 3 T

At 3 T, the effective wavelength of the RF field is comparable to the dimension of the human body, resulting in B1 standing wave effects and extra variations in phase. This effect is accompanied by an increase in B0 field inhomogeneity compared to 1.5 T. This combination results in nonuniform magnetization preparation by the composite MLEV weighted T2 preparation (T2 Prep) sequence used for coronary magnetic resonance angiography (MRA). A new adiabatic refocusing T2 Prep sequence is presented in which the magnetization is tipped into the transverse plane with a hard RF pulse and refocused using a pair of adiabatic fast‐passage RF pulses. The isochromats are subsequently returned to the longitudinal axis using a hard RF pulse. Numerical simulations predict an excellent suppression of artifacts originating from B1 inhomogeneity while achieving good contrast enhancement between coronary arteries and surrounding tissue. This was confirmed by an in vivo study, in which coronary MR angiograms were obtained without a T2 Prep, with an MLEV weighted T2 Prep and the proposed adiabatic T2 Prep. Improved quantitative and qualitative coronary MRA image measurement was achieved using the adiabatic T2 Prep at 3 T. Magn Reson Med, 2006. Published 2006 Wiley‐Liss, Inc.

2017 ACC Expert Consensus Decision Pathway for Transcatheter Aortic Valve Replacement in the Management of Adults With Aortic Stenosis: A Report of the American College of Cardiology Task Force on Clinical Expert Consensus Documents

James L. Januzzi, Jr, MD, FACC, Chair Luis C. Afonso, MBBS, FACC Brendan M. Everett, MD, FACC Jonathan Halperin, MD, FACC Adrian Hernandez, MD, FACC William Hucker, MD, PhD Hani Jneid, MD, FACC Dharam J. Kumbhani, MD, SM, FACC Eva M. Lonn, MD, FACC Joseph Marine, MD, FACC James K. Min, MD

Low operative mortality achieved with surgical septal myectomy role of dedicated hypertrophic cardiomyopathy centers in the management of dynamic subaortic obstruction

Treatment of progressive heart failure, due to left ventricular (LV) outflow tract obstruction and elevated intraventricular systolic pressures, has been a major component of hypertrophic cardiomyopathy (HCM) disease management for 50 years [(1–3)][1]. Throughout this time, septal myectomy has

Coronary MR angiography at 3T during diastole and systole

To investigate the impact of end‐systolic imaging on quality of right coronary magnetic resonance angiography (MRA) in comparison to diastolic and to study the effect of RR interval variability on image quality.

The apparent inversion time for optimal delayed enhancement magnetic resonance imaging differs between the right and left ventricles.

BACKGROUND Delayed post-contrast magnetic resonance (MR) imaging involves suppression of signal from myocardium using inversion times (TI) between 150-225 ms, when the myocardium appears dark and fibrotic scar appears bright. We noticed that at a TI optimized for signal suppression of the left ventricle (LV), the right ventricle (RV) appeared brighter. PURPOSE The purpose of this study was to evaluate the TI for signal suppression in RV compared to LV, and to try and identify the cause of this observation. Methods. We studied 31 patients (ages ranged from 17-79 years, 11 females) who had an MR scan on a 1.5 T GE scanner. Delayed post-contrast short-axis images were obtained 20 minutes after injection of 0.2 mmol/kg of intravenous gadolinium chelate. TI optimization was performed by acquiring a range of TI times within a single breath hold, in increments of 25 msec. The TI time that resulted in lowest signal for the RV arid LV was recorded. RESULTS With the imaging sequence employed, the TI leading to LV signal suppression ranged from 150-225 ms. At the TI that resulted in LV signal suppression, the corrected signal from the RV was significantly higher as compared to the LV (29 +/- 13 au vs. 15 +/- 8 au, p < 0.001). The findings were similar using only the body coil. The TI required to suppress the RV was usually < or =150 msec. The observation persisted before and after gadolinium infusion. CONCLUSION The TI for myocardial signal suppression appears to be different between LV and RV. Potential mechanisms include partial volume averaging with fat or blood pool (related to increased trabeculation) in the RV. Alternatively, increased blood pool signal (within Thebesian veins or arterioluminal communications) in RV compared to LV leads to altered TI times due to similar partial volume effects.

Computed tomography in the evaluation for transcatheter aortic valve implantation (TAVI)

If left untreated, symptomatic, severe aortic stenosis (AS) is associated with a dismal prognosis. Open-heart surgical valve replacement is the treatment of choice and is associated with excellent short and long-term outcome. However, many older patients with multiple co-morbidities and anticipated increased surgical risk are excluded from surgical intervention. For these patients, transcatheter aortic valve implantation (TAVI) is emerging as a viable treatment alternative. Transcatheter valvular heart procedures are characterized by lack of exposure and visualization of the operative field, therefore relying on image guidance, both for patient selection and preparation and the implantation procedure itself. This article describes the role of multi-detector row computed tomography (MDCT) for detailed assessment of the aortic valve, aortic root, and iliac arteries in the context of TAVI.

Automated Identification of Minimal Myocardial Motion for Improved Image Quality on MR Angiography at 3 T

OBJECTIVE Imaging during a period of minimal myocardial motion is of paramount importance for coronary MR angiography (MRA). The objective of our study was to evaluate the utility of FREEZE, a custom-built automated tool for the identification of the period of minimal myocardial motion, in both a moving phantom at 1.5 T and 10 healthy adults (nine men, one woman; mean age, 24.9 years; age range, 21-32 years) at 3 T. CONCLUSION Quantitative analysis of the moving phantom showed that dimension measurements approached those obtained in the static phantom when using FREEZE. In vitro, vessel sharpness, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were significantly improved when coronary MRA was performed during the software-prescribed period of minimal myocardial motion (p < 0.05). Consistent with these objective findings, image quality assessments by consensus review also improved significantly when using the automated prescription of the period of minimal myocardial motion. The use of FREEZE improves image quality of coronary MRA. Simultaneously, operator dependence can be minimized while the ease of use is improved.