A fast and relatively cheap cardiovascular MR (CMR) scan is a cost-effective way to scan large volumes of patients with a wide range of suspected heart conditions, said researchers from Peru in a presentation on 26 May at the EuroCMR 2017 meeting in Prague.
CMR performed with the ultrafast protocol not only changed clinical management in one-third of patients, it revealed a new, unsuspected diagnosis in 20% of them, leading to a complete change in management. For another one-third of patients no additional cardiac testing of any kind was needed.
"We showed that this ultrafast CMR protocol can be used to accurately diagnosis patients leading to changes in clinical management," said Dr. Katia Menacho in a statement accompanying release of the study. "The protocol takes one-third of the standard scan time at a fraction of the cost."
Effective but time-consuming
CMR is the gold standard for diagnosing many cardiovascular diseases because it can assess structure and function, as well as myocardial scarring to assess the likelihood of another heart attack.
The problem is its high cost and lack of availability in many institutions. For example, in Peru only two public hospitals offer CMR, Menacho said, and each facility performs 12 scans on a single day during the week. Public hospitals that lack MRI facilities refer their cases to one of five private hospitals that offer the scans at a cost of $600 to $800 U.S. (537 to 716 euros) each. And "it takes up to three months to approve the paperwork, delaying diagnosis and treatment," Menacho said.
The Impact of Noninvasive CMR Assessment (INCA)-Peru study was created to develop and test an ultrafast CMR protocol that could increase adoption of CMR in Peru by enabling more patients to be scanned, the authors wrote. The study was an international academic and political collaboration between Peru, the U.K., the U.S., and Brazil.
An initial protocol was developed at University College London (UCL) that reduced average scan times from 60 to 10 minutes. The noncontrast protocol was used successfully in Thailand to assess cardiac and liver iron overload in patients with thalassaemia major. The protocol was adapted for use in the INCA-Peru study by adding gadolinium contrast, which brought the average time per scan up to 15 to 20 minutes in a pilot study performed at UCL.
100 patients in 2 days
For this study, the CMR protocol with contrast was tested over two days at two hospitals in Peru, in a setting that also served as a training course for local cardiologists, radiologists, and technologists. The study included 100 patients with suspected cardiomyopathy as well as 11 healthy controls. All of the patients were under the care of a cardiologist and had not previously undergone CMR.
There were no complications related to the scans, and all of the scans were diagnostic, although two patients had repeat scans -- owing to the failure of contrast delivery in one, and to confirm unsuspected cardiac amyloidosis in a second patient. Gadolinium-based contrast agents were administered to 95% of patients. The 5% of patients not receiving gadolinium had iron overload.
Each CMR scan took an average of 18 minutes and cost $150 U.S. (134 euros). Common underlying diagnoses included hypertrophic cardiomyopathy in 21% of patients; nonischemic dilated cardiomyopathy in 17% of patients; and ischemic cardiomyopathy in 11%. Twenty additional diagnoses including tumors, congenital heart disease, myocardial iron overload, amyloidosis, vasculitis, and apical thrombus, the researchers reported.
Changed management
CMR had a big effect on the patient cohort, altering clinical management in 33% of patients, and revealing a new, unsuspected diagnosis in 20% of patients, which led to a complete change in management, the group reported. No further cardiac testing was needed in 30% of patients, the team added.
"We showed that this ultrafast CMR protocol can be used to accurately diagnosis patients leading to changes in clinical management," Menacho said in her statement. "The protocol takes one-third of the standard scan time at a fraction of the cost."
The study team plans to follow the patients for two years to assess the effect of diagnosis by ultrafast CMR on long-term morbidity and mortality.
"Accurate diagnoses provided by CMR have reduced morbidity and mortality in Europe and we hope to find the same in Peru," Menacho said. "If we show long-term benefits on prognosis we will seek support from the Peruvian government to provide ultrafast CMR at more hospitals in Peru. The accurate diagnosis provided by CMR should lead to more targeted patient care and better outcomes."
The study was funded by the U.K. Foreign & Commonwealth Office. EuroCMR 2017 is being held from 25 to 27 May in Prague at the Clarion Congress Hotel Prague.
