The aorta and inferior vena cava (IVC) are two hypoechoic, pulsatile structures found on an ultrasound screen to the left of midline, making their identification difficult without precise probe positioning and measurements.
Mistaking IVC/Ao ratio for left atrium dilation could result in inaccurate systolic blood pressure readings and potentially misguided medication decisions, leading to inaccurate systolic readings and possibly leading to incorrect treatment decisions altogether. This should give us all cause for great concern!
Aorta
The Aorta is the largest artery in the body. It’s characterized by thick walls and hypoechoic structure with regular pulses; located inferior to renal arteries and reaching to below diaphragm level. Serving as major blood vessel of abdomen it carries oxygen-rich blood from heart to bowels.
Ultrasound scans offer expectant mothers an accurate way to determine gestational age (CRL – crown-rump length) and due date (LMP – last menstrual period). Furthermore, ultrasounds detect any anomalies or complications in the fetus’ development – especially important evaluation criteria are the aorta and its surrounding structures.
Aortic dissection is a serious medical condition that can be easily detected using ultrasound imaging. Aortic dissection occurs when the walls of the aorta become compromised through tears or inflammation responses, potentially causing it to bulge or rupture resulting in serious medical consequences. Transthoracic echocardiography and abdominal aorta ultrasound techniques can both be used for diagnosing this condition; especially the latter as it allows users to easily identify its signature characteristic view–the suprasternal notch view – for easy identification of this diagnosis.
This ultrasound view is often used by veterinarians for measuring the LA:Ao ratio, as well as to estimate fetal cardiac size. There are various techniques for taking this measurement; there can be much disagreement on which approach should be used; some vets prefer basal short-axis views while others favor right parasternal approaches.
Comparative to other screening tests, PA/AO ratio had the lowest detection rate for fetuses with TGA (transposition of the great arteries). Most TGA fetuses have abnormally aligned great vessels and an abnormal PA/AO ratio around 3VV; however, its accuracy requires skilled operators; in addition, this ratio does not detect concomitant ventricular septal defects (VSDs).
When conducting a pelvic echo, the probe should remain perpendicular to the patient’s abdominal wall for optimal results. If gas in the transverse colon is blocking your view, apply constant downward pressure and rock back and forth to displace it; this will enable you to see both aorta and IVC; in thoracic aortas, however, IVC won’t appear circular but will instead lie off center on your screen.
Inferior vena cava
The inferior vena cava (IVC) is a large vein that transports deoxygenated blood from the lower body back up towards the heart, returning oxygenated blood for processing by your heart. It forms one half of two large veins called Venae Cavae that also include superior Venae Cavae which transport blood from head, neck, arms and chest back towards heart for processing by heart.
Blood vessels that connect to the IVC include the hepatic portal vein, lumbar veins, and azygos vein. Additionally, it connects with the thoracic aorta through the coronary sinus, a small vessel connecting blood from left ventricle to thoracic aorta via coronary sinus.
Blood clots that form deep within your legs or pelvis – known as deep vein thrombosis – may break loose and travel to your lungs, blocking blood flow and leading to serious health complications, including pain, difficulty breathing and death. An IVC filter can help protect you by trapping these clots before they reach the lungs.
Before your IVC filter procedure, your doctor will administer sedation through an IV line in either your arm or hand to help keep you calm and relaxed throughout. This may also involve shaving the area where the procedure will occur in order to reduce pain while simultaneously improving results. Your physician may also remove some hair prior to beginning.
An IVC filter is a small metal device designed to prevent blood clots from traveling from your veins into your lungs, placed using minimally invasive interventional radiology procedures. Your doctor will make a small incision in either your neck or groin before inserting a thin tube called a catheter into the major vein leading to your IVC and using fluoroscopy, guide its path towards inferior vena cava in your abdomen.
Once your doctor has identified an ideal spot, they will insert the filter. It will adhere securely to the walls of your blood vessel so it can trap any potential blood clots. After your procedure is over, they will remove the catheter and take you directly to a recovery room before sending you home shortly thereafter.
Peripheral arteries
Your physician will use Doppler technology to examine your abdomen, thighs, pelvis, legs, arms and groin during an ultrasound scan. By viewing blood flow and identifying any anomalies they can help create a personalized treatment plan to improve your condition and avoid future complications.
Your physician will evaluate fetal growth and development by measuring CRL (crown-rump length), DPD (distance from one side of the head to the other) as well as your LMP (last menstrual period date) to establish gestational age of your unborn fetus, in order to make accurate predictions regarding its future development.
Measurement of the LA:Ao ratio can take many forms. Practitioners may prefer measuring it from either long or short axis perspectives; results from these views often differ significantly; however, results of this study show that LA:Ao is a valid screening tool for identifying outflow tract abnormalities in fetuses.
Researchers conducted an in-depth examination of 107 fetuses ranging in gestational age from 16-24 weeks. Diameter measurements for both pulmonary artery and aorta were taken using three-vessel view (V3VV), then the PA/AO ratio compared with that of normal fetuses; results demonstrated that it could detect 86% of outflow tract abnormalities while having the lowest detection rate when it came to transposition of great arteries (TGA).
MCA and UmA artery Doppler impedance indices were also evaluated, which are closely associated with neonatal acidosis and could predict adverse outcomes for fetuses in humans. Early identification is key as timely interventions could prevent severe neonatal acidosis incidence rates among human fetuses; the authors recommend conducting MCA and UmA Doppler indices analysis at least twice every two weeks during third trimester pregnancies to decrease incidence and improve neonatal outcomes and lower risk post delivery; researchers suggest conducting tests at least twice each two weeks until delivery takes place.
Vascular structures
Many ultrasound exams incorporate an examination of vascular structures. This allows physicians to quickly identify any issues with blood flow, such as clots and blockages, so they can develop a treatment plan accordingly. Point-of-care ultrasound (POCUS) can also be used for diagnosing life-threatening emergencies like abdominal aortic aneurysm or dissection – conditions which if left untreated quickly could prove fatal.
One of the more frequently assessed vascular structures on ultrasound scans is the Aortic Arch (AO). This section of Aorta lies on a transverse plane perpendicular to the fetal spine at stomach-umbilical vein level; it serves as the primary route for blood from leaving the heart and entering the descending Aorta as well as being an important site of fetal hemodynamics.
An aortic arch can be difficult to visualize on ultrasound due to being surrounded by lung/air, making its presence hard for ultrasound waves to penetrate through. Furthermore, an overly hypertrophied pyelonephric duct could obscure its visibility further.
Because of this, AOs are sometimes neglected; however, it’s essential for screening for aortic disease when combined with proper pattern recognition techniques.
Point-of-care ultrasound has demonstrated its utility for diagnosing aortic disorders among those presenting nonspecific symptoms, but due to an absence of standardization in its interpretation it has led to significant variations in assessment of dimensions such as LA:AO ratios as well as frame rates for LA:AO ratios. Unfortunately this means significant variations occur among interpretations.
Ultrasound can detect many anomalies, however its accuracy varies significantly when treating chronic pain. Therefore, pain management specialists advise combining ultrasound with other imaging modalities, such as MRI or CT scans. You could also try an AO scan, which analyzes over 120,000 frequencies to detect “biomarkers,” energetic points on your body that provide biofeedback information about how well the body is working as well as what factors could be leading to changes in behavior or performance.
