Help with the following In 2015, Ant Financial's MYbank (an offshoot of Jack Ma's Alibaba company) was looking to extend services to rural areas in China by providing small loans to farmers. Microloans have always been costly for financial institutions to offer to the unbanked (though important in development) but MYbank believed that fintech innovations such as using the internet to communicate with loan applicants and judge their credit worthiness would make the program sustainable.

41 What are the clinical features of a ruptured sinus of Valsalva?

42 Does dobutamine (dose range 2.5-10 g/kg/min) cause significant tachycardia?

43 Are beta-blockers indicated in heart failure; if yes, in all cases or in selected cases?

44 Why does long-term treatment by digitalis cause gynaecomastia?

45 Why do toxic doses of digoxin (which cause a decrease in excitability of cardiac tissue) cause arrhythmias, whereas therapeutic levels of digoxin (which cause increase in excitability) cause no arrhythmias?

46 Hypokalaemia is one of the complications of digitalis. In treatment we give K. How does the hyperkalaemia enhance the digitalis toxicity?

47 Why should we measure serum potassium before we start digoxin?

48 The intravenous administration of loop diuretics such as furosemide relieves pulmonary oedema rapidly. Is this due to arteriolar vasodilatation reducing afterload which is an action that is independent of its diuretic effect? I ask this because I have been told that this drug has no effect on arterioles (except on efferent arterioles of the kidney), but rather a venodilatatory effect. What could be the cause of such different opinions?

49 There have been a number of recent publications concerning aspirin versus warfarin trials. Would you recommend prescribing warfarin for secondary prevention of coronary heart disease in patients suffering from their first myocardial infarction (MI)?

50 Is it true that in future the ApoA : ApoB ratio will be used to predict the risk of coronary artery disease more efficiently than low-density lipoprotein (LDL)?