CardioExchange Archive

CardioExchange is pleased to reprint selections from Dr. Richard Lehman’s weekly journal review blog at BMJ.com. Selected summaries are relevant to our audience, but we encourage members to engage with the entire blog.

NEJM  26 July 2012  Vol 367

Using CTA to Rule Out MI and Ischemia in the ED (pg. 299):  ROMICAT stands for Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography, and this is the second trial so far—hence ROMICAT-II. The primary end-point was time to discharge from hospital and this 1,000 person randomized trial shows that you can cut it from a median of 26.7 hours to 8.6 if you do immediate CT scans on all patients presenting with possible cardiac chest pain. At least that’s what Table 3 says. In the Abstract the figure given is a mean reduction of stay by 7.6 hours. A good illustration of the difference between the median and the mean, and a rare example of a study underselling itself. But questions remain. Part of the rationale of the study was that reliance on ECG biochemical markers in acute chest pain can leave residual diagnostic uncertainty, yet the rate of adverse cardiovascular events within 28 days in the two groups was exactly the same—zero. Moreover, those who had immediate coronary CT had more downstream diagnostic tests, not fewer. The only thing they gained was earlier discharge home; costs were identical, and on the down side, the CT group notched up a sizeable dose of ionizing radiation. Given that we can’t quantify the harm from this, here’s a situation where patients with acute chest pain have a very difficult choice to make as they arrive in the emergency room, wondering if their end has come. “Do you want a high radiation scan or would you be willing to stay here a bit longer to avoid it?” I wonder how many ER doctors would even ask them.

n-3 Fatty Acids for Preventing CV Events in Patients with Dysglycemia (pg. 309): The acronym for the next trial is ORIGIN, and it looked at two things which were thought promising to prevent cardiovascular events in 12,536 subjects with dysglycaemia: n-3 fatty acids and/or basal insulin. In fact, neither of these had any effect on CV events. But maybe this is a good moment to remind you of the three categories of “dysglycaemia” as currently defined. There is type 2 diabetes, defined by a persistent fasting blood glucose of 7.0 mmol/L or more. There is impaired fasting glucose, defined as a fasting glucose level between 6.1 and 7.0; and there is impaired glucose tolerance, defined as a rise in blood glucose to between 7.8 and 11.1 two hours after a glucose load. All of these states confer some additional cardiovascular risk.

Basal Insulin and CV Outcomes in Those with Dysglycemia (pg. 319): So let’s move on to the second and more interesting part of this 2×2 factorial trial which tested the hypothesis that reducing fasting glucose to 5.3 or lower by means of injected basal insulin glargine will lower cardiovascular events in all these patients. The logic of this must be familiar to all of you: 5.3 is the level of fasting glucose that represents the threshold for increased macrovascular risk. So let’s see what happens if we try to lower everyone’s sugar to 5.3 with insulin. I’ve already told you the answer—nothing. And this is important. Firstly because it is one more bit of evidence that pushing down sugar levels below quite a high level (perhaps above 8 mmol/L) is a futile strategy for risk reduction, and secondly because it shows that exogenous insulin itself does not increase cardiovascular risk. It does however increase the risk of severe hypoglycaemic events, from 0.3 to 1.0 per 100 person-years.

Lancet  28 July 2012  Vol 380

Citicoline for Acute Ischemic Stroke (pg. 349): Some ideas seem so good that they just keep on being tested, to repeated destruction. Stem cells for cardiac repair; HDL raising for lowering cardiovascular events; neuroprotective drugs for better stroke outcomes. We would all love them to work, but in trial after trial, they bomb. Here, in a multi-centre European trial, citicoline, which works in animal models of stroke, fails to have any effect in 2298 patients with moderate-to-severe acute ischaemic stroke, though it’s already got a licence in several European countries. In The Marriage of Heaven and Hell (c.1793) William Blake has Isaiah over for dinner and asks him, “does a firm perwasion that a thing is so, make it so?” The prophet replies, “All poets believe that it does, & in ages of imagination this firm perwasion removed mountains.” Alas, what may be a fine rule for poets and prophets is not a very good one for drug licensing bodies and medical practitioners.

BMJ  28 July 2012  Vol 345

Hypertension Misperception and Medication Adherence: Another thing that never seems to change is public misperception of high blood pressure as something that is caused by stress and which gives rise to symptoms. Here is a systematic review of qualitative studies from a total of 16 countries—more of these please!—and everywhere the myth is the same. Lay people of all nations share the delusion that if you take away the stress, down goes the blood pressure and the symptoms disappear, so you can stop taking the tablets. Not that doctors are free of myths about hypertension either, but that is another matter, and deserves a similar level of qualitative enquiry.

Predicting the 10-Year CV Risk in the U.K.: And another risk score I won’t be using much is QRISK2, because it is so rare for me to initiate long-term treatment these days, and I tend to be of the “statins for everyone” persuasion anyway. But if you care deeply about better discrimination of risk, this external validation study shows it’s better than Framingham for the UK population—by 5% in men and more in women.

Arch Intern Med  23 July 2012  Vol 172

CV Risk Among Those with Atherothrombosis Who Live Alone (pg. 1086):

When love, with one another so
Interinanimates two soules,
That abler soule, which thence doth flow,
Defects of lonelinesse controules.
Wee then, who are this new soule, know,
Of what we are compos’d, and made,
For, th’Atomies of which we grow,
Are soules, whom no change can invade.

So John Donne, in one of his greatest poems, The Extasie, describes the fusion of souls achieved by sexual love. Some think the poem was addressed to his 17-year-old wife, Anne; and certainly when she died after giving birth to their twelfth child at the age of 33, he became obsessed with his own death, which he believed might re-interinanimate their souls. When he eventually sickened at the age of 58, he duly prepared his tomb, and had himself depicted lying within it before he rose to preach his last sermon. Loneliness in older persons is a predictor of functional decline and death. In this paper, it is also found to be broadly true of people over the age of 45 who have atherosclerosis and who are living alone.

Six-Minute Walk Test for Predicting CV Events in Patients with Stable CHD (pg. 1096):  In the Heart and Soul Study, “Distance walked on the 6 Minute Walk Test predicted cardiovascular events in patients with stable coronary heart disease. The addition of a simple 6MWT to traditional risk factors improved risk prediction and was comparable with treadmill exercise capacity.” Interesting: and I bet if you look in five years’ time, cardiologists will still be doing as many treadmill tests and as few six minute walks as they do now.

Patient Preference in the Decision to Place ICDs (pg. 1104): When questioned, patients with heart failure often rate better quality of life as more important than longer duration of life, but they are seldom offered the choice. Implantable cardioverter-defibrillators improve overall survival figures in patients with systolic heart failure and QRS prolongation, but few patients are aware that they are therefore more likely to experience a slow death from breathlessness than a sudden death from ventricular arrhythmia. This survey of AHA physicians (12% response rate) shows that cardiologists don’t, by and large, discuss this with their patients. They know best: ICDs save lives, and earn fees.