Table 2

Examples of respondents’ comments for statements describing changes in management for the three statements (3, 5 and 9) that were in consensus in both the first survey and the modified survey and the two statements (1 and 8) that were in consensus in the modified survey only

Statement 3
Patients with OHCA
Importance of management change
CMR differentiates causes of cardiomyopathy (IHD vs not). We use it regularly in patients post out-of-hospital cardiac arrest.
I have seen many cases of out-of-hospital cardiac arrest in which the use of CMR has made a diagnosis or significantly altered the diagnosis. Diagnostic refinement in the light of CMR findings also frequently results in changes in drug or device treatment, and often highlights the need for family screening. The improved anatomical, morphological, and tissue characterisation that CMR allows drives the benefit of CMR over echo and allows better identification of the cause of out-of-hospital arrest.
Quality of supporting evidence
I don't think it has been proved that clinical outcomes are better with a CMR strategy.
CMR is unlikely to alter the immediate management of these patients. However if the cause is unclear after echo and enzymes then CMR is helpful but I am not aware of any studies specifically assessing this.
Statement 5
Patients with unobstructed arteries on angiography
Importance of management change
Agree. Unobstructed coronaries with elevated troponin need diagnostic resolution and CMR is helpful.
These patients are difficult to manage and often given incorrect diagnosis and especially different theories by different doctors during same admission.
I have direct experience of the benefit of CMR in this area. Therefore, I strongly agree with statement 5. CMR with LGE is especially useful and I have seen many instances when CMR after acute MI with ‘normal’ coronary arteries has helped diagnosis, differentiating between distal vessel occlusion, LV clot, myocarditis and Takotsubo cardiomyopathy. The results of CMR in this patient group have also directly affected my management of this group of patients including drugs used and length of stay.
MRI is clinically useful in this situation in my experience and occasionally makes a very useful change to management.
Quality of supporting evidence
Unfortunately again no RCT to indicate benefit of CMR.
Statement 9
Patients with postinfarct LV thrombus
Importance of management change
Thrombus is poorly assessed by echo with many inconclusive reports in my experience locally.
I strongly agree with this statement as I have experience of many patients in which echo demonstrated no LV thrombus that was subsequently found on CMR. This personal experience correlates with the studies quoted in the text of the statement.
Quality of supporting evidence
This statement is true but whether this leads to better patient outcomes is uncertain.
Statement 1
Patients with poor prognosis after PPCI
Importance of management change
All patients who have suffered an acute MI and subsequently undergone PPCI should receive aggressive secondary prevention. Thus, even though CMR can help refine prognosis I do not feel that this additional information would lead to any significant changes to prescribing for secondary prevention. Enhanced confidence in CMR findings (compared with echo) and refinement of prognosis with respect to infarct size, MVO and MSI may help physicians discharge/follow-up patients more appropriately.
All patients should have aggressive secondary prevention.
Quality of supporting evidence
While I agree with the evidence presented, there is no evidence to support the assertion the CMR findings lead to better outcomes for patients as there have been no trials assessing this.
I don't think it has been proved that CMR compared with echo leads to improved patient outcomes.
While MVO and MSI are markers of prognosis, LV systolic function remains the most important prognostic factor, which can be assessed with echo. We need interventions based on CMR parameters which improve prognosis.
Cost of CMR in relation to perceived benefit
Agree but not sure current restricted availability and high cost and only modest anticipated change in clinical action justifies wholesale change from echo that also predicts risk well.
Statement 8
Patients with MVD
Importance of management change
I'd accept perfusion scanning or DSE as adequate tests for ischaemia and would really only specifically request CMR if there were additional diagnostic questions.
Total revascularisation at one sitting with FFR guidance may render this unnecessary.
Stress CMR in my experience is better than SPECT or stress echo. This is because the improved prognostic and diagnostic accuracy helps physicians manage, with confidence, non-significant coronary disease medically rather than invasively. There are also additional benefits of CMR, for example definition of scar for CRT implant or for VT ablation. It can be helpful to ‘archive’ this information for latter use if the patient is going to receive a device such as an ICD that may preclude latter CMR scanning.
Quality of supporting evidence
Evidence shows improved diagnostic accuracy compared with SPECT and DSE, but not in this specific cohort.
The evidence for ischaemia testing in the PPCI era does not really exist. There are no studies comparing MRI in this context with other modalities and definitely no RCT comparing CMR versus another modality.
  • CMR, cardiovascular magnetic resonance; CRT, cardiac resynchronization therapy; DSE, dobutamine stress echocardiography; FFR, fractional flow reserve; ICD, implantable cardioverter defibrillator; IHD, ischaemic heart disease; LGE, late gadolinium enhancement; LV, left ventricular; MI, myocardial infarction; MSI, myocardial salvage index; MVD, multivessel disease; MVO, microvascular obstruction; OHCA, out-of-hospital cardiac arrest; PPCI, primary percutaneous coronary intervention; RCT, randomised controlled trial; SPECT, single-photon emission CT; VT, ventricular tachycardia.