Aspirin has persisted as the bedrock of secondary prevention for coronary artery disease. Vitamin K antagonists when added to aspirin provide superior efficacy in patients with acute myocardial infarction (AMI) albeit at the cost of excess bleeding. One is therefore wary of adding warfarin to aspirin post AMI despite reduction in reinfarction. Aspirin alone at a low dose is associated with a fairly low incidence of serious bleeding. The addition of a second anti-platelet agent again enhances efficacy but at the price of increased bleeding. The addition of an anticoagulant to dual antiplatelet therapy also substantially increases serious bleeding.
A manufacturer sponsored double blind trial has studied more than 27,000 patients of stable cardiovascular disease. The COMPASS trial randomized patients to rivaroxaban (a direct factor X inhibitor) alone at a dose of 5 mg twice day, aspirin alone at 100 mg a day and a combination of rivaroxaban and aspirin at a dose of 2.5 mg twice a day. The primary outcome was cardiovascular death, stroke or myocardial infarction. The study was stopped after 23 months follow up because there was significant advantage with the combination regimen of rivaroxaban and aspirin versus aspirin or rivaroxaban alone.
For decades treatment of type 2 diabetes (T2D) has relied solely on treating high blood sugar level reflected by the percentage of glycated hemoglobin (HbA1C). But in the last decade it has been realized that cardiovascular outcomes remain largely unchanged despite pulling down blood sugar and HbA1C. Many clinical trials have reported that merely lowering plasma glucose level with anti-diabetes drugs does not modify cardiovascular risk factors. Cardiovascular disease accounts for 80% deaths in T2D. Lowering high blood pressure and correcting dyslipidemia therefore are very important approaches for treating T2D. Increased plasma level or hyperglycemia however has come out as a weak risk factor for cardiovascular complications.
The only study to show improved cardiovascular outcomes in T2D was the UKPDS trial in which the drug metformin caused a reduction in clinical events. But the UKPDS included only 342 obese patients of T2D to come to the conclusion of better cardiovascular efficacy with metformin. The ADOPT study on the other hand which included 818 patients of T2D reported that metformin resulted in cardiovascular events than patients getting glyburide, although the difference was not significant.
The main action of metformin is to cut down production of glucose by the liver. It’s ability to sensitize muscle or adipocyte to insulin is feeble in the absence of weight loss. Metformin has no effect on beta cell function in the pancreas, which is the main pathophysiological disturbance resulting in progressive hyperglycemia in T2D. No wonder both UKPDS and ADOPT failed to reduce HbA1C in the long term because of progressive beta cell destruction.
It is time to concentrate on the pathophysiological disturbances in the body that result in T2D. Increased blood sugar is ultimately caused by 8 pathophysiological abnormalities, also called the ‘Ominous Octet.’ It has been well known that beta cell failure and insulin resistance in muscle and liver are the core pathophysiological defects in T2D. In fact people with impaired glucose tolerance have already lost more than 80% of beta cell function and are maximally insulin resistant. The other pathophysiological defects include the fat cell (accelerated lipolysis), gastrointestinal tract (incretin deficiency), alpha cell (hyperglucagonemia), kidney (increased glucose reabsorption) and the brain (insulin resistance). It is obvious that a drug that acts against all or most of these mechanisms will be effective or a combination of drugs.
Heart failure is a debilitating and life threatening disease in which the heart is unable to adequately pump blood around the body leading to symptoms of breathlessness, fatigue and fluid retention. About half of heart failure patients have reduced ejection fraction when assessed by 2D echocardiography.
Systolic heart Failure continues to torment millions of patients across the world despite enormous progress in drug treatment over the last 30 years. There was no drug capable of cutting down death rate available in the 1980’s when my Mum was suffering from breathlessness, swollen feet and tiredness due to ischemic cardiomyopathy. The CONSENSUS study reporting mortality benefit with enalapril got published just then and I desperately acquired the medicine for my Mum but she sadly found it too toxic. The smallest dose would nauseate her. I was crushed, for there was no alternative then. George Orwell died of TB in the 1940’s; streptomycin had been discovered but Orwell simply could not tolerate the antibiotic despite getting hold of it in the United States. It seems incredible now but there was no treatment for heart failure till the mid 1980’s.
My heart sank as I rose to speak in the mid-term Delhi cardiology mid year meting because there was just a handful of delegates left to hear me out. I had wanted very much to stress the redundancy of studies done in the recent past because hardware used then differed from drug eluting stents (DES) currently implanted. Clinical outcomes with second generation DES have improved substantially. Looking at the almost bare hall I for a moment thought that Hurricane Irma had changed course and was barreling to New Delhi. I had never imagined a Delhi cardiology meeting unable to draw less than a dozen physicians at 7 o’clock in the evening. And I had all these years always imagined Delhi to be a city having a fair share of intellectual worth.
I wanted to tell them about the PLATO trial (published in 2009) that randomized more than 18,000 patients of acute coronary syndrome to clopidogrel or ticagrelor. The researchers had reported that Ticagrelor combined with aspirin reduced the composite clinical outcome of death, myocardial infarction, and stroke from 11.7% to 9.8% as compared to clopidorel and aspirin. An absolute reduction of 1.9%. . The absolute decrease in mortality at the end of one year was just 1.4% (5.9% to 4.5%); a relative 22% reduction. Hence 71 patients have to be treated with ticagrelor for one year to prevent one death.Ticagrelor was however associated with more non CABG related major bleeding than clopidogrel (4.5% vs. 3.8%; p=0.03), including more fatal intracranial bleeding. It should also be noted that a loading dose of 300 mg clopidogrel was administered in only 60% of patients in the clopidogrel group.
Rene Favaloro had written in 1993 to Dr. Denton Cooley: “ Besides being an outstanding surgeon, you are a good human being, and ……to be good is enough.”
More than a half century ago Rene Favaloro, a Sicilian born in Argentina, performed his first coronary artery bypass graft (CABG) operation on 9th May 1967. He and his colleagues had performed 100 CABG operations in 3 years and Favaloro has since been considered the “father” of CABG, even though the first actual procedure was performed by a German immigrant, Robert Goetz, in May 1960. Goetz anastomosed the right internal thoracic artery to the right coronary artery. But Goetz’s colleagues considered the operation “not only highly experimental, but also unwarranted” and prevented him from performing a second CABG procedure. The first CABG was done on a 38-year-old patient who lived for more than a year. There was however no autopsy and details of the surgery were not documented and so Goetz’s achievement went unrecognized until the Society of Thoracic Surgeons, in its Annals of June 2000, acknowledged that Goetz did “the first successful clinical operation on May 2, 1960.”
Goetz also is also credited with developing the intra-aortic balloon pump in the 1960’s, which is still used to give mechanical support in patients with poorly contracting harts.
Antibiotics have been the bedrock of treating bacterial infections and thereby saving millions of lives, beginning with the discovery of penicillin by Sir Alexander Fleming in the 1940’s. The first randomized trial done in medicine used streptomycin in patients with tuberculosis, again in the 1940’s. Fleming had stated that if one were to use an antibiotic, it should then enough of it should be used. Fleming shared the Nobel Prize for medicine and physiology in 1945 with Howard Florey and Ernst Chain In September 1928, Fleming returned after a month to find that a mold had destroyed a culture of Staphylococcus aureus. The mold was Penicillium notatum. Penicillin, the antibiotic was later purified and isolated, and used extensively in World War II. Fleming died of a heart attack in 1955.
In his acceptance speech Fleming narrated a fictional scenario in which a man suffering from a streptococcal sore throat takes inadequate penicillin; and subsequently is responsible for the death of his wife by resistant bacteria. The reality as we have learnt is that Streptococcus pyogenes never developed resistance to penicillin.
Current World Health Organization guidelines insist that it is essential to “finish a course” of antibiotics to avoid triggering more virulent forms of disease. In fact physicians all over the world follow the mantra of completing the prescribed “antibiotic course.”
Till the COURAGE trial was published , it had remained unclear whether initial treatment with percutaneous coronary intervention (PCI) plus optimal medical therapy (OMT) was superior to OMT alone. Patients with retrosternal pain on effort that disappeared by stopping or taking nitrates were considered to have stable angina (SA). The patients had to have at least 70% stenosis in one proximal coronary artery and objective evidence of myocardial ischemia (substantial ST segment depression or T wave inversion on the resting ECG or inducible ischemia with either exercise or pharmacologic vasodilator stress). Or the patients needed to have at least 80% block and classic angina without provocative testing. All patients were provided aspirin 81 to 325 mg per day or 75 mg of clopidogrel per day if there was aspirin intolerance. Medical ant ischemic treatment in both groups included long acting metoprolol, amlodipine, and isosorbide dinitrate along with lisinopril or losartan for secondary prevention. Simvastatin was given to lower low-density lipoproteins to 60 -85 mg%. Successful PCI was defined as normal coronary artery flow and less than 50% stenosis after balloon angioplasty and less than 20% stenosis post stent implantation. However very few patients received drug-eluting stents (DES).
The researchers concluded that as an initial management strategy PCI added to OMR did not reduce the primary composite end point of death and myocardial infarction (MI) as compared with OMT during follow up of 2.5 to 7 years. The degree of angina relief was significantly greater with PCI. Limitations of the study include the preponderance of male patients (85%), 86% of patients were white, and almost all patients got DES. The COURAGE trial was a randomized study involving 2287 patients of stable angina.
Survivors of acute myocardial infarction (AMI) with impaired left ventricle systolic dysfunction face the prospect of sudden cardiac death (SCD) largely due to the presence of premature ventricular complexes (PVC’s) and ventricular tachyarrhythmia. The incidence of mortality increases 4 folds if there are more than 10 PVC’s in an hour. However anti-arrhythmic medicines proved to be hazardous in these patients. More than 2 decades ago, a major randomized trial confirmed that the anti arrhythmic drugs flecainide and encainide actually increased mortality as compared to placebo in patients who had had an AMI in the past. The CAST trial ensured that anti arrhythmic were no longer used to treat PVC’s and non-sustained ventricular tachycardia.
The 2017 Tour de France (TdF) has begun, and Geraint Thomas has won the first stage. Thomas is the first Welshman to wear the famed yellow jersey. The TdF is a grueling long distance cycling race that covers 3,500 kilometres over 23 days (consisting of 21-long day segments or stages) , in France and bordering countries. The competition is more than a century old and has been held every year except during the 2 World Wars. It is the most physically demanding sporting event of the world.
The most infamous cyclist is of course Lance Armstrong, who won the Tour 7 times, and that too back to back, from 1999 to 2005. The incredible wins gave him legendary status apart from earning millions of dollars and the chance to cycle along the President of the United States. Armstrong would defiantly rebuke any concern of doping directed at him. “I have been tested 500 times, and have never been found positive”. Rumors continued to swirl around him, the American government initiated an inquiry and finally the US Anti Doping Agency stripped him off all titles including every 7 Tour win. He has also been banned from participation in any sporting event whatsoever.
One of the most dramatic and important achievements of the last century was the discovery of insulin in 1921-1922 in the University of Toronto. The patent remarkably got to be sold for a mere one dollar. Today a single vial of long acting insulin analogue costs almost $ 200 in the USA. North America has 7% of the world’s diabetic population but accounts for more than 50% of insulin sale, whereas China accounts for 25% of the world diabetic population but accounts for only 4% of insulin sales. Insulin sales could have been worth more than 20 billion dollars worldwide last year.
The story of the discovery has garnered a mythical hue. A 29-year-old surgeon Frederick Banting was assisted by undergraduate student named Charles Best in experiments with dogs that resulted in a crude insulin extract. The laboratory facilities were provided by the respected physiologist J.J.R. Macloed.The crude extract was refined by J B Collip, a biochemist. The crude insulin extract was injected in the first patient of diabetes in January 1922. This resulted in mild lowering of blood sugar, but the result was exciting enough for Eli Lilly in the US and Connaught Labs in Canada to begin industrial production of the wonder drug that would prove a life saver for patients of type 1 diabetes.
The sixth largest bank in Spain collapsed a few days ago. The failing of the bank is being compared to the collapse of the 150 years old Lehman Brothers in 2008. The collapse of the Spanish bank should be a matter of concern because the EU is the second largest economy in the world with the Euro being the second most used currency on the planet. Many investors have begun predicting the largest market crash sometime at the end of this year or early next year. More than 100 million working age Americans are unemployed. Warren Buffet apparently has $ 86 billion cash to buy cheap stocks after the anticipated great crash. Vehicle sales in the US have been going down each month the last 5 months in the US. The 2008 stock market crash will be a picnic compared to the imminent stocks collapse.
The future is not exactly rosy where the economy is concerned, particularly US fiscal health despite Mr. Trump’s recent more than $ 250 billion deal with the Saudis, a large proportion of which is money for arms and ammunition. America will continue with its spectacular efforts to amplify wars on the planet.
Sir James Black significantly contributed to the history of medicine by discovering not one but 2 great medicines. The second one was cimetidine a reasonably powerful anti peptic ulcer drug that he figured out would be effective based on the fact that histamine a powerful stimulant of gastric acid secretion was used as a diagnostic test to detect the susceptibility of a person to develop a peptic ulcer.
But probably more revolutionary was the development of propranolol in the 1960s by Black who studied medicine in Oxford. Black realized way back in the 1950’s that one way of tackling narrow arteries was to reduce heart rate and force of contraction of the human heart. In other words lower the need of oxygen. This led to his discovery of propranolol. Black won the Nobel prize in 1988 for “discoveries of important principles for drug treatment”.
Low cardiac output syndrome following cardiac surgery is not uncommon and is consequent to systemic inflammation by heart lung machine, vasoconstriction or reperfusion injury. Treatment is usually with parenteral inotropes such as beta-adrenergic agonists and phosphodiesterase inhibitors once low output sets in. The flip side with inotropes is that they can increase both oxygen consumption of the myocardium and trigger atrial or ventricular arrhythmias. Observational studies have reported higher rates of postoperative myocardial infarction, stroke renal dysfunction and death as compared to those patients not receiving inotropes.
Levosemenedan is a novel inotrope that does not increase oxygen consumption, has prolonged duration of action, and increases myocardial contraction by sensitizing calcium binding to troponin C. It also acts as a vasodilator. Small-randomized trials have shown postoperative mortality to be lowered with levosemendan as compared to dobutamine, milrinone or placebo. But these studies were not powered to detect survival with levosemendan.
Fractional flow reserve (FFR) albeit highly accurate in determining the physiological relevance of an intermediate coronary block is still not widely used in most cath labs of the world. Data from 2008 to 2009 has revealed that FFR was used in only 6% of indeterminate lesions in the United States. Results of FAME and FAME 2 trials have shown significant reduction in major adverse cardiovascular events with FFR guided coronary intervention in patients with stable coronary disease. There was no significant reduction in mortality in the FAME trial.
Elective percutaneous coronary intervention (PCI) has always included at least an overnight stay due to fears of acute complications such as myocardial infarction, bleeding or vascular complications. Over the years interventional cardiologists have acquired greater confidence with improved hardware and better percutaneous techniques whilst doing PCI procedures. The risks of major adverse events have gradually been shrinking and are actually quite low. Most major adverse events occur within 6 hours of PCI. A same day discharge (SDD) protocol has gradually emerged after single center randomized and observational SDD experience. Overnight stay remains standard practice after a PCI.
A meta analysis collected data from almost 13,000 patients undergoing PCI. The study included 7 randomized trials (2738 patients) and 30 observational studies (10,065 patients). Clinical outcomes consisted of myocardial infarction, death, target lesion revascularization (TLR) and majority of patients suffered from stable angina.