An Overview on Cardio Vascular System (Hypertension)

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1. CARDIOVASCULAR SYSTEM (CVS) Dr. SHAIK KAREEMULLA Associate Professor Department of Pharmacy Practice M. M. College of Pharmacy (MMDU)

2. H eart is located in the front of chest region. It is situated slightly behind to the left of sternum (also called breastbone ). The ribcage protects heart. Everyone’s heart is of slightly different sizes. Generally, adult hearts are about the same size as two clenched fists, and children’s hearts are about the same size as one clenched fist . Heart pumps blood through three types of blood vessels: Arteries carry oxygen-rich blood from heart to body’s tissues. The exception is pulmonary arteries, which go to lungs. Veins carry oxygen-poor blood from tissues to heart. Capillaries are small blood vessels in which body exchanges oxygen-rich and oxygen-poor blood.

3. Heart is the main organ of cardiovascular system, a network of blood vessels that pumps blood throughout the body. It also works with other body systems to control heart rate and blood pressure. Average weight of the heart in an adult male is 300-350 gm while that of an adult female is 250-300 gm. Heart is divided into four chambers: right atrium; left atrium (both lying superiorly) & right ventricle; left ventricle (both lying inferiorly).

4. The atria are separated by a thin partition called interatrial septum, while ventricles are separated by thick muscular partition called interventricular septum. The blood in the heart chambers moves in a carefully prescribed pathway: venous blood systemic circulation → right atrium → right ventricle → pulmonary arteries → lungs → pulmonary veins → left atrium → left ventricle → aorta → systemic arterial supply .

5. Cardiac output (CO) is the blood volume the heart pumps through systemic circulation over a time period; measured in liters per minute .  There are various parameters utilized to assess cardiac output comprehensively, but one of most conventional approach involves multiplying the heart rate (HR) and the stroke volume. CO = SV x HR  The average stroke volume of 70 kg individual is 70 mL A normal resting heart rate is between 60 to 100 beats per minute Cardiac output in humans is generally 5-6 L/min

6. Heart walls are the muscles that contract (squeeze) and relax to send blood throughout body . A layer of muscular tissue called the septum divides heart walls into the left and right sides. H eart walls have three layers: Epicardium: Protective outer layer. Myocardium: Muscular middle layer. Endocardium : Inner layer. Heart conditions are among most common types of disorders affecting people. In the United States, heart disease is a leading cause of death for people of all genders.

7. Atrial fibrillation :  Irregular electrical impulses in atrium. Arrhythmia :   A heartbeat that is too fast, too slow or beats with an irregular rhythm. Cardiomyopathy :   It mainly deals with u nusual thickening, enlargement or stiffening of heart muscle. Congestive heart failure :   When heart is too stiff or too weak to properly pump blood throughout body. Coronary artery disease:  Plaque or fat buildup that leads to narrow coronary arteries. Heart attack (Myocardial I nfarction):  A sudden coronary artery blockage that cuts off oxygen to part of heart muscle. Pericarditis:  Inflammation in heart’s lining (pericardium).

8. L ifestyle changes to keep heart healthy: DASH stands for Dietary Approaches to Stop Hypertension. Achieve and maintain a  healthy weight  for gender and age. Eat a heart-healthy diet  with plenty of fruits, vegetables and whole grains. Exercise  moderately for at least 150 minutes per week. Limit your sodium intake. Manage   stress  with healthy strategies like  meditation . Quit smoking  and using tobacco products; also avoid  second hand smoke exposure .

9. HYPERTENSION (HTN) Dr. SHAIK KAREEMULLA Associate Professor Department of Pharmacy Practice

10. An estimated 1.28 billion adults aged 30–79 years worldwide have hypertension, most are living in low and middle income countries. An estimated 46% of adults with hypertension are unaware that they have the condition. Approximately 1 in 5 adults ( 20 %) with hypertension have it under control. Hypertension is a major cause of premature death worldwide. One of the global targets for non-communicable diseases is to reduce the prevalence of hypertension to 33% by 2030 .

11. Blood pressure is defined as pressure exerted by the blood against the walls of the arteries . Arteries carry the oxygenated blood from the heart to other parts of the body. Blood pressure normally rises and falls throughout the day and is measured in millimeters of mercury (mm Hg).

12. Signs & Symptoms: People with high blood pressure (usually 180/120 mmHg or higher) can experience symptoms including: severe headaches. chest pain. dizziness. difficulty breathing. nausea. blurred vision. anxiety . nose bleeds. a bnormal heart rhythms.

13. Risk Factors: Age:   The risk of high blood pressure increases with age. Until about age 64 , high blood pressure is more common in men. Women are more likely to develop high blood pressure after age 65 . Race:  High blood pressure is particularly common among Black people. It develops at an earlier age in Black people than in White people. Family history:  You're more likely to develop high blood pressure if you have a parent or sibling with the condition .

14. Obesity: Excess weight causes changes in the blood vessels, the kidneys and other parts of the body. Being overweight or having obesity also raises the risk of heart diseases due to cholesterol levels accumulation. Tobacco use: Smoking, chewing tobacco immediately raises blood pressure for a short time. Tobacco smoking injures blood vessel walls & speeds up process of arteries hardening. C hronic conditions: Kidney disease, diabetes, sleep apnea are some of conditions that can lead to high blood pressure. Pregnancy: A fter 20 weeks of pregnancy, women suddenly develops high blood pressure, called Pre-eclampsia.

15. Causes: Primary hypertension, or essential hypertension: In adult patients , there's no identifiable cause of high blood pressure. This type of high blood pressure is known as primary hypertension or essential hypertension. It tends to develop gradually over many years. Plaques buildup in the arteries , called atherosclerosis, increases the risk of high blood pressure . Note: Sometimes just getting a health checkup causes blood pressure to increase. This is called white coat hypertension.

16. Secondary hypertension: This type of high blood pressure is caused by an underlying condition. Adrenal gland tumors. Blood vessel problems at birth, congenital heart defects. Kidney diseases. Obstructive sleep apnea. Thyroid problems. Medications such as immunosuppressants, NSAIDs and oral contraceptives (birth control pills). Illegal drugs, such as cocaine and amphetamines .

17. Pathophysiology: One of  described factors for development   of essential  hypertension is patient genetic  ability  towards  salt response . About 50 to 60% of patients  are salt sensitive ; therefore tend to develop  hypertension. Various mechanisms  for development of  hypertension includes I ncreased salt absorption resulting in volume expansion,  I mpaired response of renin-angiotensin-aldosterone   system,   I ncreased activation of sympathetic nervous system. These changes lead to   increasing total peripheral resistance and afterload which  in-turn leads to development of hypertension.

18. Pathophysiology of Hypertension (RAAS)

19. Diagnosis: Most cases of hypertension are asymptomatic and are diagnosed incidentally on blood pressures recording or measurement. Some cases present directly with symptoms of end-organ damage stroke-like symptoms or hypertensive encephalopathy, chest pain, shortness of breath and acute pulmonary edema . The ACC recommends at least two office measurement on at two separate occasions to diagnose hypertension. The ESC/ESH recommends three office BP measurements at least 1 to 2 minutes apart, and additional measurements only if the initial two readings differ by greater than or equal to 10 mmHg. BP is then recorded as average of last two readings.

20. The patient should remain seated quietly for at least 5 minutes before taking blood pressure, proper  technique is necessary. The  blood pressure cuff should cover  80% of the arm circumference because  larger or smaller pressure cuffs can falsely under-estimate or over-estimate blood pressure readings. Ambulatory blood pressure measurement is the most accurate method to diagnose hypertension and also aids in identifying individuals with masked hypertension and white coat effect.

21. Treatment / Management: M anagement of hypertension subdivides into pharmacological and non-pharmacological management. Non-pharmacological, lifestyle management are recommended for all individuals with raised BPs regardless of age, gender, comorbidities or cardiovascular risk status. Lifestyle changes alone can account for up to 15% reduction in all cardiovascular-related events. Patient education is paramount to effective management and should always include detailed instructions regarding weight management, salt restriction, smoking management, adequate management of obstructive sleep apnea and exercise. 

22. Pharmacological therapy consists of: Angiotensin-Converting Enzyme inhibitors ( ACEi ) A ngiotensin Receptor Blockers (ARBs ) D iuretics (usually thiazides ) C alcium channel blockers (CCBs ) B eta-blockers (BBs ) These drugs are instituted taking into the account of age, race and comorbidities like presence of renal dysfunction, LV dysfunction, heart failure and cerebrovascular disease. 

23. JNC-8 recommends the following: Starting pharmacological therapy for individuals with DM and CKD with BP greater than or equal to 140/90 mmHg to therapeutic target BP less than 140/90 mmHg Starting pharmacological therapy for individuals 60 years of age and over with BP greater than or equal to 150/90 mmHg to therapeutic target BP less than 150/90 mmHg Starting pharmacological therapy for individuals 18-59 years of age with SBP greater than or equal to 140 mmHg to therapeutic target SBP less than 140 mmHg

24. Individuals with DM and non-black population, treatment should include a thiazide diuretic, CCB, and ACEi /ARB. Individuals in the black population, including those with DM, treatment should include a thiazide diuretic and CCB. Individuals with CKD, treatment should be started with or include ACEi /ARB, and this applies to all CKD patients irrespective of race or DM status.

25. ACC recommends the following Ten-year atherosclerotic cardiovascular disease (ASCVD) risk should be estimated. Anti-hypertensive medications are usually initiated when BP readings are persistently greater than or equal to 140/90 mmHg. High-risk population (diabetics, CKD, individuals with ASCVD) or in those individuals with 10 -year ASCVD risk greater than or equal to 10% , therapy can be initiated at lower BP cutoffs. The goal of treatment is to keep blood pressures in as close to normal range i.e., BP less than or equal to 130/80 mmHg.

26. Treatment Planning: Polytherapy has become the mainstay of treatment and is endorsed and recommended by ACC. There have been two main approaches: Either initiating two or more drugs (usually an ACEi  or an ARB along with thiazide diuretic and calcium channel blocker) simultaneously, or Stepwise titration approach with single therapy being up-titrated to maximum dosage before initiating a second drug .

27. Both have been successful in improving patient outcomes provided there is adequate compliance and treatment adherence. All the societies recommend at least an 8 to 12-week  duration of anti-hypertensive medication before assessing BP control and reviewing patient for complications. There is a general consensus that home BP measurements or ABPM should be checked at or before initiation of therapy and then three months after starting therapy for monitoring and documentation of adequate BP control.

28. Toxicity and Adverse Effect Management: Side effects are usually self-limited and include hypotension (more common with calcium channel blockers (CCBs) and ACEi / ARBs), electrolyte imbalances, pedal edema (more common with CCBs) and renal dysfunction. Renal dysfunction and electrolyte imbalance especially hyponatremia; hyperkalemia are frequent with ACEi and ARBs and need to be monitored periodically until the achievement of static levels of Cr, K, and Na.

29. For patients suffering severe side effects like symptomatic hyperkalemia or hyponatremia, syncope, acute kidney injury (AKI), treatment needs to be discontinued, and in-patient management is advised. Nephrologist and cardiologist opinions also need to be sought in such cases. Once the issues settle, treatment needs to be re-instituted gradually and cautiously with careful monitoring and frequent follow-ups. Angioedema has been a potentially life-threatening side effect of ACEi and ARBs in susceptible individuals and warrants the prompt discontinuation, therefore considered as a lifelong contra-indication for ACEi / ARB usage.

30. Complications Coronary heart disease ( CHD) Myocardial infarction (MI)  Stroke (CVA), either ischemic or intracerebral hemorrhage Hypertensive encephalopathy Renal failure, acute versus chronic Peripheral arterial disease Atrial fibrillation Aortic aneurysm Death (coronary heart disease, vascular disease, stroke-related)