should we trust and follow evidence based guidelines?

Guidelines authored by Medical bodies like American Heart Association are strongly followed in our cardiology practise in India as there is lack of trial data conducted in India. I as a practising cardiologist strongly advocate Guideline based therapy. 

However, lately I have been surprised by the recommendations of the new guidelines on various topics. This is because of the change in recommendations which are totally contrary to the previous version of the guidelines. 

Let me cite some examples:

  1. The ATP-3 guidelines strongly advocated Goal based therapy for LDL-cholesterol management. They suggested that LDL cholesterol should be maintained below 100 mg/dl in patients with diabetes  or coronary artery disease. These recommendations were followed by Cardiologists all over the world for the last 12-13 years. However, the new guidelines on Lipid management released by the ACC 2014 mentions that there is no trial to suggest that the target-based therapy of LDL cholesterol works. Instead they advocate high dose statin to be given in patients with high risks and to bring down the LDL cholesterol levels by 50%. This is a drastic change which then calls into question the data on which the earlier ATP guidelines were based.

2.  Beta-blockers were advocated in earlier version of guidelines for treatment of Vasovagal syncope. Even, in my personal experience I have number of patients who felt better with beta-blockers and had remission in their symptoms. However, the new guidelines mentions beta-blockers as Class III (harmful).

3. Amiodarone was advocated earlier for acute treatment of  recurrent ventricular tachycardia (VT). However the new European guidelines on Arrhythmias in ACS mentions that it should be avoided and instead Cardioversion should be preferred.

 

The drastic change in the new recommendations/ guidelines  for treatment of the various disorders (as mentioned above in examples) is unexpected and surprising. The reasons for these may be availability of new trial data or not a thorough evaluation of the trials by earlier committees.

Whatever the reasons, for us as practising Clinicians, patient safety is paramount. Thus, Strict adherence to the new guidelines is advisable and to be followed (till the time we have data available from trials conducted in India on Indian patients). However the therapy should be discussed with and individualised for each patient.

 

 

Warning Symptoms Precede Sudden Cardiac Arrest in most cases.

Warning symptoms, notably chest pain and dyspnea, occur during the 4 weeks preceding sudden cardiac arrest (SCA) in at least half of cases involving middle-aged adults, suggests a new study. The warnings are usually ignored, observe researchers, with few patients phoning 911 in response to what is almost always a fatal event.

The analysis is based on the Oregon Sudden Unexpected Death (SUD) cohort which was published online December 22, 2015 in the Annals of Internal Medicine.

It suggests that sudden death may not be as sudden as we have been thinking till now. There were people who had their symptoms not only in the 24 hours that preceded the arrest, but also in the 4 weeks that preceded their event.

 

The Oregon SUD study is a large, prospective, community-based study of deceased and surviving patients who had an SCA in the Portland, Oregon metropolitan area. The analysis included 839 patients between 35 and 65 years of age with SCA whose prodromal symptoms could be comprehensively assessed.

Of the 839 patients, 430 patients or 51% of the cohort experienced at least one symptom within the 4 weeks preceding their arrest. Men and women experienced prodromal symptoms with equal frequency at 50% vs 53%, respectively.

Symptoms also started more than an hour before SCA onset in 80% of patients; but in 147 of these patients, symptom onset occurred more than 24 hours before their arrest. Among this subgroup of patients, 93% had recurrent new episodes of symptoms during the 24 hours preceding their arrest.

The main symptom was chest pain, documented in 199 patients,” or 46%, Marijon observed. Of those, 76% had “intermittent typical angina,” he said.

Another 18% of patients had dyspnea as their apparent prodromal symptom; about one-third of this group had established congestive heart failure or a pulmonary condition.

 

What Can Be Done

An early call to 911 was associated with better survival odds in the current study suggesting that there is a potential to enhance short-term prevention of SCA by targeting public awareness of SCA.

Source: Warning Symptoms Can Often Precede Sudden Cardiac Arrest