The heart and kidneys share a powerful two-way connection: the heart supplies oxygen-rich blood that allows the kidneys to filter waste and balance fluids, while the kidneys regulate blood pressure and volume to ease the heart’s workload. When one organ falters, the other is quickly affected, creating cycles of decline seen in conditions like metabolic syndrome, cardiorenal syndrome, and the broader cardio-renal-metabolic axis. Because these systems are so intertwined, early recognition of risk factors and a comprehensive, coordinated approach to care are essential for protecting overall health and preventing serious complications.
At CardioVascular Health Clinic in Oklahoma, expert care for both heart and kidney health starts with a highly experienced, multidisciplinary team of interventional cardiologists, vascular surgeons, and interventional radiologists working together. Through innovative, minimally invasive procedures and cutting‑edge imaging technologies delivered in modern outpatient centers, our specialists bring advanced solutions to the vascular, cardiovascular, and renal access needs of our patients. Whether it’s early detection through precision diagnostics or expertly maintained AV fistulas for dialysis, our multi-pronged, patient-centered approach ensures coordinated care that elevates outcomes and protects the vital connection between your heart and kidneys.
The heart and kidneys are deeply interconnected, forming a partnership that keeps the body’s circulation, fluid balance, and blood pressure in harmony. Each organ depends on the other: the kidneys filter the blood and regulate fluid levels, while the heart provides the steady flow of oxygen-rich blood that makes kidney function possible. Together, they maintain stability across multiple systems and ensure the body’s internal environment stays balanced.
The kidneys are primarily known as filters, removing waste products, excess water, and electrolytes from the blood, but their role goes far beyond filtration; they are also critical regulators of blood pressure and fluid volume, functions that directly support heart health.
One of the most important mechanisms the kidneys control is the renin–angiotensin–aldosterone system (RAAS). When blood flow to the kidneys drops, they release an enzyme called renin, which sets off a cascade that produces angiotensin II. This hormone narrows blood vessels and triggers aldosterone release, signaling the body to retain sodium and water. The result is an increase in blood volume and blood pressure, ensuring the heart and other organs receive adequate circulation.
The kidneys also interact with hormones released by the heart itself. When the heart senses it is being stretched by extra volume, it releases natriuretic peptides such as ANP and BNP. These hormones encourage the kidneys to excrete sodium and water, helping lower blood volume and pressure. In this way, the kidneys respond to the heart’s signals and maintain balance.
Just as the kidneys influence blood pressure and volume to ease the heart’s workload, the heart provides the force that powers kidney function. By pumping oxygenated blood through the circulatory system, the heart ensures that the kidneys receive the flow and oxygen they need to filter the blood effectively.
This relationship is most evident in the process of glomerular filtration, the first step in cleansing the blood. For filtration to occur, the kidneys require a steady level of blood pressure and volume, both of which are maintained by healthy heart function. Adequate cardiac output means the kidneys can filter efficiently, removing wastes and keeping the internal environment stable.
In short, the heart fuels the kidneys with oxygenated blood, and the kidneys fine-tune the body’s blood pressure and volume to support the heart. It is this constant back-and-forth communication that keeps the entire cardiovascular system in balance.
The relationship between the heart and kidneys is one of balance: each organ supports the other to keep blood pressure, circulation, and fluid balance stable. But when one begins to fail, the consequences can quickly ripple outward; kidney dysfunction can strain the heart, and heart dysfunction can impair the kidneys, setting off a chain reaction of decline.
For example, when the kidneys falter, complications like chronic kidney disease (CKD) can lead to anemia, mineral imbalances, and dangerous electrolyte shifts, all of which force the heart to work harder. CKD also promotes vascular calcification and toxic buildup in the blood, directly damaging heart muscle and rhythm.
On the other hand, when the heart weakens—whether from heart failure, reduced output, or venous congestion—the kidneys receive less oxygen-rich blood and filtration declines. This fluid retention and reduced clearance of waste products then circle back to further tax the heart.
It is this back-and-forth deterioration that makes the cardio-renal connection so critical. Doctors now recognize a few key conditions within this connection: metabolic syndrome (a cluster of risk factors that set the stage), cardiorenal syndrome (when the heart and kidneys are caught in a cycle of decline), and the broader cardio-renal-metabolic axis, which looks at how the heart, kidneys, and metabolism all affect one another.
Metabolic syndrome is one of the most important precursors to both heart and kidney disease. It is defined as a cluster of risk factors that occur together.
Having three or more of these risk factors qualifies as metabolic syndrome.
For the heart, metabolic syndrome accelerates cardiovascular disease through hypertension, arterial stiffening, dyslipidemia, and inflammation. These factors increase the risk of coronary artery disease, heart attack, stroke, and heart failure. Obesity and insulin resistance further contribute to chronic inflammation and hormonal imbalance, raising the risk of conditions like heart failure with preserved ejection fraction (HFpEF).
For the kidneys, the same processes cause damage at the filtration level. Hypertension injures delicate glomeruli, insulin resistance heightens pressure within them, and chronic inflammation promotes scarring and decline in kidney function. Obesity and atherosclerosis compound the problem, narrowing renal arteries and worsening blood flow.
Cardiorenal syndrome (CRS) is the medical term for what happens when dysfunction in one organ directly causes dysfunction in the other. Unlike metabolic syndrome, it is not just a collection of risk factors, but an outcome—a clinical condition where the vicious cycle between the heart and kidneys is already underway.
CRS arises from hemodynamic shifts, neurohormonal activation (RAAS and the sympathetic nervous system), inflammation, and oxidative stress. Once triggered, it locks both organs into a feedback loop of worsening function: failing kidneys make the heart weaker, and a failing heart accelerates kidney decline.
Type 1: Acute heart event causing acute kidney injury.
Type 2: Chronic heart dysfunction leading to progressive kidney disease.
Type 3: Acute kidney injury triggering acute heart dysfunction.
Type 4: Chronic kidney disease leading to chronic heart problems.
Type 5: Systemic illnesses like diabetes or sepsis causing both simultaneously.
Today, many researchers view the heart, kidneys, and metabolism as part of one integrated axis, sometimes called cardio-renal-metabolic (CRM) syndrome or cardiovascular-kidney-metabolic (CKM) syndrome. This perspective recognizes that these conditions rarely occur in isolation.
By framing these conditions as interconnected, the CRM/CKM model underscores the importance of early detection and comprehensive treatment. Metabolic syndrome is upstream, cardiorenal syndrome is downstream, and the axis ties them all together.
Because the heart and kidneys are so closely connected, treating one without considering the other can leave patients vulnerable. Many of the risk factors that set the stage for disease—such as high blood pressure, insulin resistance, and inflammation—appear together as metabolic syndrome, which is highly modifiable. By addressing these early with weight management, blood pressure and glucose control, cholesterol management, and healthy lifestyle changes, patients can significantly reduce their risk of cardiovascular disease and kidney failure. Early recognition is key to preventing the downstream complications that make care more complex.
Once dysfunction begins, management becomes far more challenging. Cardiorenal syndrome is difficult to treat because therapies that benefit one organ can stress the other.
These complexities are a big reason why multidisciplinary care—integrating cardiology and nephrology into a whole-patient approach—is essential.
Expert dialysis access, including the creation and long-term maintenance of arteriovenous (AV) fistulas, with ongoing ultrasound surveillance and preventive care in collaboration with nephrologists.
Cross-system monitoring, with the ability to identify and treat related risks such as peripheral artery disease and coronary artery disease, which are especially common in patients with kidney failure.
Safe, efficient procedures like AV fistula creation and other vascular treatments performed in a state-of-the-art outpatient surgical setting, reducing infection risk, cost, and recovery time compared to hospitals.
Holistic care models focused on developing long-term relationships with patients and close peer collaboration with other specialists to develop tailored care plans that consider the full picture of heart, kidney, and vascular health.
By focusing on the cardio-renal-metabolic axis as a whole, CardioVascular Health Clinic ensures patients receive not just expert procedures, but coordinated, compassionate care designed to protect both heart and kidney health for the long term.
At CardioVascular Health Clinic, patients benefit from a multidisciplinary team of cardiologists, vascular surgeons, and interventional radiologists who bring unmatched expertise to cardio-renal care. Using innovative, minimally invasive treatments in a state-of-the-art outpatient setting, CardioVascular Health Clinic delivers safer procedures, faster recovery, and better long-term outcomes for patients all across Oklahoma.
If you’ve been diagnosed with kidney or heart disease, schedule an appointment with CardioVascular Health Clinic today and discover the difference experienced, comprehensive care can make in your overall health.
