| What parameters are controlled by beta blockers in the initial medical treatment of dissection? | reducing heart rate and blood pressure to the lowest amounts that will still maintain adequate end-organ perfusion | Acute Type B dissection is mostly subjected to medical treatment unless complicated. Irrespective of surgical or endovascular intervention, medical therapy to control blood pressure and pain is essential Initial Medical Therapy • Initial management of dissection is directed at pain control and limiting the propagation of dissection by reducing the aortic wall stress. Aortic wall stress is affected by the velocity of ventricular contraction (dP/dt), the rate of ventricular contraction and blood pressure • Initial medical treatment with beta blockers controls these 3 parameters by reducing heart rate and blood pressure to the lowest amounts that will still maintain adequate end-organ perfusion. | 586 | definition | 1.000 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | Aortic wall stress is affected by the velocity of ventricular contraction (dP/dt), the rate of ventricular contraction and blood pressure • Initial medical treatment with beta blockers controls these 3 parameters by reducing heart rate and blood pressure to the lowest amounts that will still maintain adequate end-organ perfusion. | 2 | page=2,block=7 | 0.700 | valid |
| What does Type A dissection involve? | the intrapericardial aorta regardless of the site of intimal tear | If clinical examination or CT angiography suggests involvement of innominate artery, common carotid arteries, subclavian arteries, and iliac arteries, an additional vascular ultrasound examination is performed. Conventional catheter based coronary angiogram and aortogram are not needed in diagnostic work up of acute dissection • In a stable patient with low index of suspicion of dissection, D-dimers can be assessed. Normal levels of D-dimers virtually rule out dissection. IMH and PAU may still be present. In dissection, the level of D-dimers is immediately very high, compared with other disorders in which the D-dimers level increases gradually Type A: Dissection involves the intrapericardial aorta regardless of the site of intimal tear. It is also known as Proximal dissection | 680 | definition | 0.980 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | In dissection, the level of D-dimers is immediately very high, compared with other disorders in which the D-dimers level increases gradually Type A: Dissection involves the intrapericardial aorta regardless of the site of intimal tear. | 1 |
| What does acute aortic syndrome describe? | a constellation of life - threatening aortic diseases that have similar presentation, but appear to have distinct demographic, clinical, pathological and survival characteristics | Acute aortic syndrome (AAS) is a term used to describe a constellation of life - threatening aortic diseases that have similar presentation, but appear to have distinct demographic, clinical, pathological and survival characteristics • Blood enters through the intimal tear and separates the intima from the media and or adventitia. | 55 | definition | 0.980 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | Acute aortic syndrome (AAS) is a term used to describe a constellation of life - threatening aortic diseases that have similar presentation, but appear to have distinct demographic, clinical, pathological and survival characteristics • Blood enters through the intimal tear and separates the intima from the media and or adventitia. | 1 | page=1,block=25 | 0.700 | valid |
| What causes myocardial ischemia in the context of dissection? | Dissection process involves one or more coronary ostia | Presence of diastolic murmur of aortic regurgitation, unequal pulses, limb ischemia or neurological complications favor the diagnosis of acute dissection • If dissection is diagnosed with myocardial ischemia it should be managed on the line of dissection and thrombolytic therapy should NOT be initiated COMPLICATION CAUSATIVE MECHANISM PRESENTATION Aortic Regurgitation Loss of support and distortion of aortic valve Diastolic murmur, Severe acute regurgitation can cause heart failure and pulmonary edema Myocardial Ischemia Dissection process involves one or more coronary ostia Chest pain and ECG suggestive of myocardial infarction. | 527 | relationship | 0.970 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | Presence of diastolic murmur of aortic regurgitation, unequal pulses, limb ischemia or neurological complications favor the diagnosis of acute dissection • If dissection is diagnosed with myocardial ischemia it should be managed on the line of dissection and thrombolytic therapy should NOT be initiated COMPLICATION CAUSATIVE MECHANISM PRESENTATION Aortic Regurgitation Loss of support and distortion of aortic valve Diastolic murmur, Severe acute regurgitation can cause heart failure and pulmonary edema Myocardial Ischemia Dissection process involves one or more coronary ostia Chest pain and |
| What does a tear in the aortic intima cause? | blood enters into the media separating the layers | Aortic Dissection (AD) Commonest and Most lethal Intramural Hematoma (IMH) Penetrating Aortic Ulcer (PAU) Formation of Entrance Tear Rupture of Vasa Vasorum Ulceration of atherosclerotic plaque Tear in the aortic intima and blood enters into the media separating the layers Hematoma within the medial layer of the aortic wall without intimal injury Ulcer-like lesion in the intima eroding through the media of the aortic wall and forming localized hematoma thereoff MYOCARDIAL INFARCTION VS ACUTE TYPE A DISSECTION DIAGNOSTIC IMAGING IN ACUTE AORTIC DISSECTION • The main purpose of imaging is the comprehensive assessment of the entire aorta and its branches with primary goals of confirmation of diagnosis, classification of dissection, assessment of branch vessels, and identification of complications (aortic rupture, aortic regurgitation, and malperfusion) • Besides these, imaging is also needed to assess myocardial and valvular function, pulmonary parenchyma, and state of kidneys IMAGING AND DIAGNOSTIC ALGORITHM • Combination of ECG, Chest X-ray, Echocardiography and ECG gated CT angiography provides desired information. | 224 | relationship | 0.970 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf |
| What is important to differentiate before starting treatment for myocardial ischemia in the context of dissection? | a primary coronary event and coronary malperfusion secondary to dissection process | • Clinically, a dissection-related coronary malperfusion may present with ECG changes of primary myocardial ischemia or infarction. This may increase the likelihood of misdiagnosis and inappropriate therapeutic intervention • Before starting the treatment algorithm for myocardial ischemia, it is important to differentiate between a primary coronary event and coronary malperfusion secondary to dissection process • In dissection, pain is usually abrupt, piercing, and well localized. | 332 | relationship | 0.970 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | This may increase the likelihood of misdiagnosis and inappropriate therapeutic intervention • Before starting the treatment algorithm for myocardial ischemia, it is important to differentiate between a primary coronary event and coronary malperfusion secondary to dissection process • In dissection, pain is usually abrupt, piercing, and well localized. | 1 | page=1,block=39 | 0.700 |
| What triggers the inflammatory response in the media during an inflammatory syndrome? | blood /thrombus in the media | Coma, Paraplegia/paraparesis Mesenteric malperfusion Involvement of visceral arteries, Compression of true lumen Hypotension, abdominal distension, absent bowel sounds, shock, acidosis Renal failure Involvement of renal arteries, Compression of true lumen, Abnormal renal function tests and low output syndrome decreased urine output Acute Lower Limb Ischemia Involvement of iliac arteries, Compression of true lumen Pain in lower limbs, absent pulses, cold and pale limbs, gangrene Inflammatory Syndrome Inflammatory response to blood /thrombus in the media Fever, Leucocytosis If Acute Aortic Syndrome is suspected kindly | 530 | relationship | 0.970 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | Coma, Paraplegia/paraparesis Mesenteric malperfusion Involvement of visceral arteries, Compression of true lumen Hypotension, abdominal distension, absent bowel sounds, shock, acidosis Renal failure Involvement of renal arteries, Compression of true lumen, Abnormal renal function tests and low output syndrome decreased urine output Acute Lower Limb Ischemia Involvement of iliac arteries, Compression of true lumen Pain in lower limbs, absent pulses, cold and pale limbs, gangrene Inflammatory Syndrome Inflammatory response to blood /thrombus in the media Fever, Leucocytosis If Acute Aortic |
| Why is the heart rate kept near 80/minute in patients with significant aortic regurgitation? | as lowering the heart rate furthur may prolong diastole and aggravate regurgitation | Reasonable initial targets are a heart rate nearly 60/ minute and a systolic blood pressure between 100 and 120 mm Hg • In patients with severe aortic regurgitation, it is important to maintain a mean arterial pressure between 70-80 mm of Hg to ensure adequate end-organ perfusion. In presence of significant aortic regurgitation target heart rate is kept near 80/minute as lowering the heart rate furthur may prolong diastole and aggravate regurgitation | 371 | relationship | 0.970 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | In presence of significant aortic regurgitation target heart rate is kept near 80/minute as lowering the heart rate furthur may prolong diastole and aggravate regurgitation | 2 | page=2,block=7 | 0.700 | valid |
| What are some characteristics of the pain associated with distal dissection? | The pain is sharp, ripping, tearing, knife-like, and typically different from other causes of chest pain. | It is also known as Distal dissection • Abrupt onset of severe chest and/or back pain is the most typical feature. • The pain is sharp, ripping, tearing, knife-like, and typically different from other causes of chest pain. • Anterior chest pain is more common in acute Type A dissection, whereas back or abdominal pain is more common with Type B dissection. • The pain may migrate from its point of origin to other sites, following the dissection path • Other manifestations may include ◦Shock ◦Syncope ◦Neurological deficit including stroke and paraplegia ◦Acute congestive heart failure ◦Myocardial ischemia ◦Lower extremity ischemia ◦Renal and visceral ischemia ◦Sudden death | 117 | summary | 0.970 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | • The pain is sharp, ripping, tearing, knife-like, and typically different from other causes of chest pain. • Anterior chest pain is more common in acute Type A dissection, whereas back or abdominal pain is more common with Type B dissection. | 1 | page=1,block=25 |
| What are the typical characteristics of pain in dissection? | pain is usually abrupt, piercing, and well localized | • Clinically, a dissection-related coronary malperfusion may present with ECG changes of primary myocardial ischemia or infarction. This may increase the likelihood of misdiagnosis and inappropriate therapeutic intervention • Before starting the treatment algorithm for myocardial ischemia, it is important to differentiate between a primary coronary event and coronary malperfusion secondary to dissection process • In dissection, pain is usually abrupt, piercing, and well localized. | 432 | summary | 0.970 | https://www.icmr.gov.in/icmrobject/uploads/STWs/1726643579_1_acute_aortic_syndrome.pdf | This may increase the likelihood of misdiagnosis and inappropriate therapeutic intervention • Before starting the treatment algorithm for myocardial ischemia, it is important to differentiate between a primary coronary event and coronary malperfusion secondary to dissection process • In dissection, pain is usually abrupt, piercing, and well localized. | 1 | page=1,block=39 | 0.700 | valid |