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Music to my ears
I always have music playing in the catheter lab, whilst it drives some of my colleagues mad. Apparently, it is actually good for you, especially if you listen to Bach, Mozart or Italian Composers. It reduces anxiety and improves patient behaviour within the catheter lab and has benefits prior to coronary artery bypass grafting and during cardiac rehabilitation. As we suspected, heavy metal or techno music may be harmful.
Hans-Joachim Trappe. Heart 2010 96:1868-71.
Heart Failure and Devices
Heart failure is a growing epidemic, remote monitoring is the future, yet somehow it doesn’t make the combination interesting. If you are having trouble sleeping then you may want to have a look at this contribution to the subject.
Sarwat I. Chaudhry and others N Engl J Med 363;24
The evidence of the jeopardy associated with revision procedures on implantable devices just keeps on coming. In the REPLACE (see what they’ve done there?) registry of 1744 such events the usual hazards are identified: transvenous element to procedure, high energy device and most significant of all, an 18% complication rate in upgrade to CRT procedures.
Jeanne E. Poole and others Circulation. 2010;122:1553-1561
The case for extending the role of CRT into the less symptomatic end of the heart failure spectrum is becoming compelling. RAFT examined the incremental value of CRT in ICD recipients with impaired ventricles and broad QRS complexes. The addition of CRT reduced both heart failure and death with endpoints as impressive in the NYHA II population, as in more symptomatic individuals.
Anthony S.L. Tang and others N Engl J Med 363;25
Ablation
This AF ablation business is all very well, but what happens a few years down the line? According to this long term follow up of 75 patients undergoing paroxysmal AF ablation mostly just sinus rhythm, with 79.5% free from AF at mean 4.6 year follow up and 13% of the remainder still with some AF, but significant clinical improvement form baseline.
Feifan Ouyang and others Circulation. 2010;122:2368-2377
The decision on whether to ablate AVNRT with radiofrequency (RF) or cryo is often thought as a choice between an ablation that works, but might leave you needing a pacemaker, and one that doesn’t work, but at least won’t do any harm. In CYRANO, a randomised comparison of over 500 patients undergoing slow pathway ablation by RF or cryo, the cryo group had more recurrence (9.4 vs. 4.4%), longer procedure and fluoro times and the only persistent AV block occurred in the cryo arm. It did sting a bit less though.
Isabel Deisenhofer and others Circulation. 2010;122:2239-2245
PCI
The ongoing tedious saga of Omeprazole and Clopidogrel has hopefully ended with publication of the COGENT trial. Omeprazole (and some other proton pump inhibitors (PPI)s) inhibit the antiplatelet affects of Clopidogrel in a test tube. There were concerns that this had clinical consequences in patients following acute coronary syndromes and/or PCI who were put on dual antiplatelet therapy and a PPI to protect their gut. This was heightened by some retrospective analysis of large databases, and resulted in the European Medicines Agency advising that PPIs should be avoided in patients given clopidogrel and an alternative (H2 antagonist) used instead. Premature and unhelpful advice it seems, as the double-blind, multicentre, placebo-controlled trial of 3873 patients has confirmed. Despite stopping early due to financial problems, the primary GI end point was significantly increased in the group without Omeprazole (HR 0.34, p<0.001 i.e. a 76% relative risk reduction). There was no difference in the cardiovascular endpoint with 4.9% in the omeprazole and 5.7% in the placebo group. I hope that the EMEA will retract their advice as quickly as it was introduced, recommending the use of PPIs in patients at high risk of GI bleeding i.e. most of those on dual antiplatelet therapy.
Bhatt and others. N Engl J Med 2010;363:1909e17.
Percutaneous coronary intervention (PCI) continues to grow as the preferred strategy for revascularisation (BCIS 2009 data show that 3.24 PCI’s are performed for each coronary artery bypass graft (CABG)). One question that remains answered is what to do in patients who undergo primary PCI for an acute ST-elevation MI (STEMI) and have concurrent disease in other vessels, especially chronic total occlusions (CTO = a vessel occluded or assumed to have been occluded for more than 3 months). A few small studies have demonstrated that the immediate treatment of non-culprit lesions in patients with STEMI and MVD is associated with higher morbidity and no survival benefit. The SHOCK trial indicated that total revascularisation should be attempted in patients with cardiogenic shock and multi-vessel disease (MVD), but these are a tiny proportion of our PCI population (<2%). Consequently, expert consensus in European and UK guidelines is to recommend complete revascularisation as a staged procedure, with little supporting evidence. This can be with further PCI or with CABG and should include CTOs, if they supply viable myocardium. It is especially pertinent in diabetic patients who have more multi-vessel disease and worse outcomes.
A large 10-year registry from the Netherlands of 4506 STEMI patients has addressed some of these questions, but raises others. 33% of non-diabetic patients had MVD, compared to 51% of diabetic patients. CTOs were present in 21% of STEMI patients with diabetes and 12% of STEMI patients without. A CTO was an independent predictor of 5-year mortality (hazard ratio (HR) 2.2 – essentially 2.2x as much chance of dying). 5-year mortality was 25% for diabetics with single vessel disease, 21% in diabetics with MVD without a CTO, and 47% in diabetic patients with MVD and a CTO. These are fairly grim statistics for diabetic patients. Now we need a prospective contemporary trial of revascularisation of diabetic patients with MVD (FREEDOM is ongoing) and a prospective trial of CTO revascularisation in MVD patients.
Bimmer and others. Heart 2010;96:968-1972.
The ‘ripple effect’ is well established for many investigations and treatments. The further away you live from the centre that performs the test or procedure, the less likely you are to receive it. This has now been demonstrated in patients with acute coronary syndromes (ACS). An observational cohort study of 24,910 Danish patients with a first ACS grouped them into terciles depending on distance from the invasive centre (<21km, 21-64km and >64km). You were less likely to have angiography if you resided further from the centre and you were also less likely to have revascularisation, even if you had angiography (HR 0.82, p<0.0001). We already know that this results in worse outcomes, and this further strengthens the argument to avoid the so-called ‘postcode lottery’.
Anders Hvelplund and others. Heart 2011;97:27-32.
Imaging
The National Institute for Health and Clinical Excellence (NICE) has recommended that we stop using exercise treadmill tests (ETT) and start to use CT calcium scoring +/- CT coronary angiography (CCTA) in the assessment of patients with recent onset chest pain/discomfort of suspected cardiac origin. This will mean a sea change in the way that rapid access chest pain clinics (RACPC) are run. The RACPC were a major success, spawned out of the 2000 National Service Framework. Whilst we are all aware of the limitations of ETT, many feel they should still have a role, and that CT has yet to be established, whilst having associated (radiation) risk.
There are a couple of recent studies that may help. First, a group in Rotterdam compared CCTA with stress testing (ETT or nuclear perfusion (SPECT) scanning) in 517 patients referred for evaluation of possible coronary disease symptoms. Each patient was divided into low, intermediate or high risk, using the Duke clinical scoring system. They conclude that CTCA is most helpful (and better than ETT or SPECT scanning) in those patients of intermediate risk. Either technique was equivalent in the low risk patients, whilst high risk patients should be offered invasive coronary angiography. This correlates with NICE recommendations, though the authors conclude that additional studies, including cost/benefit analyses, must be completed before CCTA will be accepted as a first-line diagnostic test in patients with an intermediate pretest probability of coronary disease.
The second study was presented at the recent American Heart Association (AHA) meeting. The CONFIRM registry, involving about 27,000 patients, demonstrated that those with obstructive coronary artery disease (>50% stenosis) on CTCA have an adjusted hazards ratio for mortality of 2.6, compared to those with normal vessels on CTCA. Interestingly, lesions that are considered non-obstructive (<50%) and therefore unlikely to give a positive result for ischaemia on non-invasive (ETT, stress echocardiography, nuclear perfusion, or perfusion MR) or invasive testing (pressure wire) had a 1.6 adjusted hazards ratio for mortality. This intimates that these patients may be good targets for aggressive secondary prophylaxis (aspirin, statin, ACE inhibitors) and the investigators have created a risk scoring system to aid those clinicians using CT angiography.
Weustink and others. Ann Intern Med 2010; 152:630-639.
James Min and others. AHA 2010.
A Cure for Hypertension?
Occasionally, a new treatment or procedure comes along that is genuinely exciting. One recent example is a new technique for treating resistant hypertension. An Australian group used a catheter based radiofrequency device to ablate the renal sympathetic nerves in two trials, Simplicity HTN-I and II. The first trial confirmed that the device successfully and safely denervated the renal sympathetic nerves and reduced blood pressure long term, but was not randomised. The second study randomised 106 patients with resistant hypertension (systolic BP >160mmHg, despite 3 anti-hypertensive medications) to the denervation treatment, or maintenance medication. At 6 months follow-up the average systolic BP drop in the denervated group was 32mmHg, compared to no change in the maintenance group. There were no vascular complications and good safety outcomes. The patients are now being followed through for 3 years to see if renervation and recurrent hypertension occurs. Although healthy scepticism should prevail, this could transform the management of hypertension, and give interventionists something else to do.
